Good content, but please write more clearly. We have capitalization and paragraphs for a reason - they make writing clearer. Please use them properly when posting here.
To add some clarification on the ignite for combustion build up, and your statement about only using !pyro if HU is procced.
assuming !pyro+Hu. you should proc your !pyro with IB and continue to fireball till you have these conditions.
Always start with a fireball. because of the 0.5s cancel delay on HU. If you Fb->!pyro Even if only the !pyro crit you get another !pyro, since the first !pyro lands within the 0.5s cancel delay. if Both crits you get !pyro+Hu and can get lucky and get another !pyro.
This is another reason i find PoM to be overvalued, as i normally have little problems getting 2-4+ pyros into my AT combination. and even without AT its not uncommon to get 2-3+ pyro's
Also activating AT prematurely results in less than the +6s to basicly all trinkets pots and hero at pull, and should be taken into consideration.
I have also seen people suggest using IB if you get a Hu during this chain, and normally it would be 2-3 pyro in to the chain that it is suggested, i find this somewhat stupid as IB lowers your ignite by a large amount, assuming you have 2-3 pyro's in your ignite pool, you might as well combust at this point or take your chances of a higher ignite after AT reset.