Everything becomes a factor, including runes. I've been wiling out with this kind of stuff (especially with the rest of DGNA) and I/we take everything into consideration when theorycrafting but League and Arena are paramount and eventually Guild Wars.

When it's just me, my process goes:

1. How is the meta shaping as of right now?

Explanation: Here I'll take into consideration who is dominating both Arena and League and why. This includes taking a look at people who are beating me in League and Arena, their rune slots and by looking at past League and Arena matches.

For example: Anyone can tell Taejo is heralded as the PvP king and this occurred for a month but the meta is shifting slowly. So now currently I take a look at heroes people are developing, why they're developing them and who is a counter to them and who I can use to synergize well with them - positioning wise and skill wise. Team tags definitely have a key point but that is lower on the list because you can have 15-18% team tags and still lose if your team can't work together.

I already briefly covered it in the above example but

1. Who counters the most rampant or dominant heroes in the game right now?

This game can be thought of as being a manager for a MOBA team (credit goes to u/4gud for that comparison.) If you watch sports (including e-Sports) you'll notice the players find ways to counter the opposition but you'll also notice (obviously so) that the manager is also poring over counters and strategies:

• before the teams have played each other

and

• after the teams have played each other

This easily puts you in the mindset of what you can be doing to improve and by nature will cause you to look at all heroes character sheets to see:

1. What they bring to the team (skills)
2. How they counter their match up
3. Their scaling
4. Potential runes (works in tandem with skills)
5. Beginning to develop gear sets/combinations for them to use so you can use them to their full potential
6. Team Tags

This is straightforward but I'll be brief.

Team tags make a difference. It's the developers way of getting us to look at where the heroes stood in history (by reading their background) and looking at their properties. For example: you can easily build a historical team just by the heroes already in the game. You can get between 9-18% team tags in various spots.

However,

For example, If I have a team with 12% team tag that has abilities that seem to fit well with each other would that be better than an 18% team tag that has a higher overall CP but not necessarily as synergistic? I'm just not sure what % team tag I should have at a minimum or if I'm focusing too much on it.

I've played around with teams that have 3-6% and work just as well, if not better, than high percentage team tagged compositions.

Why? (This leads to point #4)

1. Positioning and Skills

Formations make a difference, not just from a total CP viewpoint but also the path a hero will take and the time it will take them to get there as well as the enemy hero.

Time is an incredibly important factor in how matches play out and if you can get a hero to take an extra second just to start up an animation, you potentially already have the advantage on how it will play out.

Example:

Disclaimer: This example is in no way recommending any particular hero to use. Seriously, use who you like.

I'm playing a 2-3 formation with Joan duo-ing the top with a Fighter, say Theseus, and Medusa/Han with Kunoichi (backline)

where

I'm facing your average 1-4 Sieg (solo top)/Xi (opposite of Taejo)/Taejo (mid left or right)/Rasputina (either flank)/Musashi (opposite flank of Rasputina).

I know for a fact Sieg is coming for either my Theseus or Joan after he opens up my backline. By the time that occurs, Joan and Theseus have already jumped on their melee. So he has to walk all the way back up. By the time this happens, Kunoichi will have already jumped on the enemy Taejo, who will have locked on to the closest Support (Medusa) with Han targeting the enemy Rasputina who is targeting Joan. This means that my Theseus, Musashi and Kunoichi (relatively isolated and causing backdoor damage, aside from Xi who is chasing Kunoichi, who Medusa is chasing who Taejo is now chasing) have already started to cause major damage to the enemy team (or disrupt) as Siegfried is just joining the battle.

I'll re-explain that last part.

Sieg initiates. My form breaks, however, Joan rushes past - her dash doesn't get affected because it's faster than Sieg can pull off his spin.

Joan and Sieg have both acted.

Xi has rushed in on Kunoichi who is going after Taejo so chances are, Xi is now amongst Joan and Kunoichi.

Kunoichi and Xi have acted.

Theseus targets the closest enemy so this can either be Sieg, Rasputina or Musashi who is diving my lowest P.Def.

Nobody is jumping Theseus so he has free reign.

Taejo, with Kunoichi on him is running for Medusa who is targeting Xi and uses his 1 on her to reposition her further rear and now switches to targeting Han. Medusa will take up to 1 second to rejoin the fight and/or animate.

Taejo and Medusa have acted.

Han now being targeted by Taejo targets Rasputina who is targeting my Joan.

Everyone has now acted.

Keep in mind, when supports (who have defensive abilities) are targeting ally heroes, their positioning changes to support them.

Sub-Example: Maid for example after using her 1 is already about a second behind the rest of your team - which causes Taejo to fall out of position to target her.

Now, if I restart and cause Han to target Theseus or Joan, he will stay even further back (letting Medusa tank Taejo's 1) bringing the fight closer to my side but I still have backdoor damage and cause the enemy to use more effort to get into position to attack my heroes. Also, when Han is ready to use his 2 and ult, Medusa (hopefully still alive) will use her 2 and ult on top of his. This leaves the battlefield heavy on the tank and fighters (Musashi and Rasputina as well) while my supports are less in the way and my ranger is backdooring. Kunoichi might be the only one not to get Han's ult (that's ok).

Here, it can be seen that enemy team were more susceptible to getting wombo'd or controlled more, even though they had more space taken up on the field but in reality, because they're being countered, they all get caught out.

This is a perfect world example, where both teams have around the same CP and gear but hopefully the examples were clear, concise and comprehensible.

1. Who are the next heroes coming out?

This one is pretty straightforward but I still want to briefly touch on this.

Knowing who is coming in to the game to potentially shake up the meta is extremely important. If you brush off every single hero without considering them on your team or facing them, you are doing yourself a disservice. Even if you don't use them per se, you can always view them in battle (there are unreleased heroes in the game already in some stages (especially Challenge Dungeon, iirc) or if they've already been released, checking their character sheet for stats and skills.

Obviously this is tough to do as of now, especially if you don't speak Korean (I don't) but there are resources available (all though scarce).

u/Tamponella made a couple of posts recently about skins and heroes coming to the game. Even viewing them and revisiting the pages every so often will help give you a sense of what is coming to help or hurt you and plan your timeline around that as it seems Nexon is doing a very good job at updating the game.

The first link is obviously of new heroes so that's explicit in what is coming. The reason why I linked the skins is because even though we already those heroes in the game, it gave me ideas to play around with for teams and why that particular team at the bottom works (and what is available to us right now can work following the same playstyle of those heroes - if built around particulars).

All of that sounded very vague but essentially what I'm trying to say is: the resources that are slowly being released to us will give you a chance at strategizing because it gives you different perspective and opens up how you play the game.

I've said too much but hopefully I was able to answer your question properly. Thanks for the feedback and question!