You are asking all the right questions, and they show you are focusing on the effective parameters (and limitations) of your equipment. That's all a Very GOOD thing.
The answer to your questions are : ... It still all depends on several factors.
Certainly accurate shot placement, and effective power levels at POI are the priority.
Understanding your rifles abilities, your abilities, your ammo's characteristics and trajectories,
Are also important.
Additionally, understanding the differences in the game you hunt changes all the parameters of the points made above. For example,
A straight on chest shot on a piegeon from your Marauder will drop them like a rock at 80+ yards.
BUT ! ! !,
that same piegeon at 50yds presenting a side profile shot, has a darn good chance of taking the hit and flying off wounded.
WHY ? ? ?
Because the heavy "stems" of the wing feathers are actually somewhat difficult to penetrate with a 30 fpe .22
Crows are even tougher. There wings are almost like Kevlar !
I've made perfect center mass hits on crows at 50 yds, and watched them fly away like they were just tickled.
But on either bird, a well placed 50-75 yd head/neck or chest shot will be far more effective., and should result in a straight drop.
Rabbits ?,... they are relatively easy to take down with just about any solid hit. Heck they will practically fall down if you miss and just throw dirt on them.
I've taken countless numbers of them at 80-100 yds with my .22 Marauder.
But Ground Squirrels
They are basically the Psycho Zombie Un-Dead,
that you never know if they will go DRT upon impact,, ... OR, ...
Run 30 yds to their burrow after taking a 50 fpe polymag hit to the brainpan.
using your .22 mrod on a raccoon or a adult opossum at 35+ yds will require a good brain or heart/lung hit.
I would say that is about the respectable limits of your .22 mrod
Your mileage may vary.