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The A_Chase function can be customized in almost any way you want, with only one major limitation. You can't make actors target dead ones. Being able to target dead actors would be incredibly useful for Archvile / necromancer style enemies. Not much else, but you get what I mean. It's incredibly difficult to make them follow dead actors without replaces the entire function.

This would require a rework of the AI systems to serve a purpose that would be better done with custom scripting anyhow. You can set monster goals or even use proxy actors to make your monsters move in the direction you want towards the corpses. The actor code is too bloated in its current state and it got that way over decades of additions and overrides-to-overrides-to-overrides-to-overrides to the point that additions should only ever be considered if there are no good alternatives.

I ended up using the second solution, as I couldn't figure out goals.
Looking back, TargetDead fits an incredibly niche use case.
Still, it would be nice to not have to find messy solutions for something so seemingly simple.

Over time we may refactor the actor code and make it more simplified, and things like this can be considered again.

If you are using ZScript, you can use a thing iterator and find the closest corpse to your enemy and just set the your_rezzing_enemy.goal to the corpse actor. As far as I know that should work.