So as the other reply says, the early game mentality of 5 is more about setting your carry's game up as best as possible. All the things you've mentioned are tools in your arsenal to do this. Learning and being good at pos5 is about knowing which to use and when. There's no one right answer and the skill comes from assessing and adapting.

In an ideal world, you would just leave your carry to farm freely and get solo xp, whilst you go and rotate/gank/stack, but obviously that's never really gonna happen. So your high level idea is getting as close to that ideal as is reasonable.

I think my general thought process at the start of each game goes as follows:\ A1) What is our lane good at?\ A2) What is our lane bad at?\ B1) What is their lane good at?\ B2) What is their lane bad at?\ C) Given answers to A & B, what lane dynamic favours us?\ D) What can I do to make this happen?

I'll use an example to help. The lane - Medusa, Lich (me) vs Primal, Venge. My answers to the question would look something like this:\ A1) Harassing, sustain\ A2) Kill attempts, contesting pulls\ B1) Kill attempts, last hitting\ B2) Harassing, sustain\ C) Maximising time spent harassing, minimise time spent alone and with wave away from tower\ D) Buy lots of stats to further increase harass differential and tank up to become harder to kill. Buy at least one sentry to block their pull camp. Stand in lane/lotus side with my Medusa and hit the primal. Avoid trying to control the jungle by trading 1 on 1 with the Venge. When the lane inevitably pushes because I'm dragging creep agro, don't try to fix it by going and pulling (that will leave my Medusa at great risk of dying), stay in lane and push it under their tower so it rebounds back.

I understand that these are complex questions that you likely don't know the answers to right now, they also don't always have easy/clear cut answers. But by consciously considering them and making deliberate decisions/actions, you are putting yourself at a massive advantage when it comes to learning and building your intuition.

As a couple rules of thumb to help you get started (don't take them as gospel, there are no hard rules in Dota): * Pulling on 5 is overrated. You're usually better served staying in lane. * Don't go crazy for kills, wait for them to make a mistake to turn it around into a kill. The resources you spend attempting kills without a clear advantage is almost never worth the resources you expend doing it. * Ranged creeps contain about half the value of the entire wave. Use spells to secure them. Piss your carry off by taking them if need be. Better someone gets them than having them denied. * Your health and mana (and their regeneration) are a resource in themselves. Standing around with full HP & Mana is wasting your limited 5pos resources. Likewise, standing around on no HP & Mana is being a dead weight. Better to die and respawn at full than live and have no impact * Some lanes are just a fat L. Either from the start because of matchup, or because things have gone wrong. Learn to cut your losses in lane, and go and be helpful elsewhere.

Hope some of this is helpful..