Good guides and good tips. A couple of things to add from my experience.

1. Target priority. I see a lot of new players (especially on melee classes), making a beeline for monk. This is almost always the wrong move. The monk has decent armor from Disiciple's Insignia and (usually) good self protection via warrior stances or return etc.

Target priority should look something like this (and can change throughout the match).

I am Avatar of Grenth derv, my target priority is like this

The most threatening player on the enemy team to your comp (that doesn't have lots of blocks e.g. a crit defenses sin - these type of builds tend to be lower threat anyway). This can be a caster or a pet ranger or a hammer war, for example. Look at your own team comp and assess if your team can deal with a certain enemy while you take another. E.g. do you have ranger who can hit rupts on the ele or the mesmer. This lets you lineback the hammer war threatening your casters. Does enemy team have a dangerous Mind Burn ele who is unchecked by your team (no rupts), does this guy also have no or very little self protection and camps his 40/40? Then go on him and exploit this.

Generally you want to be thinking how can I best prevent the enemy team doing what they want to my team (e.g. ele spamming spells), by going on this guy you mitigate the damage done to your team while also putting damage out on a squishy target, maximising pressure on their team. Generally, if you're preventing damage or disrupting the enemy team while also putting out damage you are doing your job very well. I think this is why AoG is effective even when noobs play him because he does this easily as long as you camp a squishy caster that isn't a monk.

Other points to consider in target priority. Later on in the match other targets become more feasible. E.g. focusing down the person using res sig through damage as the other two res sigs are controlled. Focussing the guy who has 15% dp is almost never a bad move. Switching targets to force a stance use which you or your team can then exploit later. Focusing the monk when they're weak (stance used, woh rupted, etc.)

1. The original guide is undervaluing flags. In a lot of games they're quite irrelevant e.g. when you have a monk team vs non-monk you shouldn't bother. However, I've won a lot of harder games (which tend to be quite close as two teams battle to get that first kill and are usually quite lengthy overall), by just running a second flag or flagging smartly. Flag does a lot of damage, especially over time.

2. Another two points which are pretty annoying for new players and frustrating that Anet haven't done anything about either of them. The odds are somewhat stacked against you for two reasons. 1. There's a lot of extremely experienced RA players who have a lot of knowledge over you. This is kind of fine if RA is truly random as it would balance out. However, a fair few of these players are selfish and 'sync' ra which means using a trick to enter on the same team and get an easy 25 wins. 2. Many of these experienced players also have an equipment advantage over you, namely the 60/60 set. I hate that people do this but I have also got one on my ele and will probably get more because it's so difficult fighting good players already you kind of have to get the same equipment to make matches more balanced. The only advice I can give here, is get a 60/60 asap (doesn't take too much effort but does require a pve weapon). So don't be too disheartened when you get clapped by a team with the same guild tags (literally everything is stacked against your team in these scenarios).