People confuse Incinerate with Disintegrate. The only similarity they have is being a channel. Incinerate is a burn multiplier, not a skill you just channel on everything until you run out of mana.
Aspect of Conflagration is important. The codex version is the same as if the Capstone was working and everything had 5 unique burns. 20% to all your burning damage while channeling, including incinerate damage itself, regardless of whether Incinerate is hitting it or not.
Since incinerate is a burn itself, so it also procs the Fire Wall enchant. Incinerate is also far larger and easier to direct against groups of enemies, so proccing even more fire walls is easy.
Incinerate, and burns builds in general, require more tanky characters because they just don’t have the burst of Crit. It’s why Fire has the warmth passive as well as Incinerate having a passive that debuffs enemy damage.