My recommendation would be to buy a PCP that meets your TYPICAL needs as closely as possible, that suits your type of shooting, that feels good in your hands, that is in your budget.
I don't recommend .177 caliber for PCPs. They're great for springers but kinda light for PCPs.
For general use the .22 is versatile, economical (cost of pellets/slugs and air usage) and with a wide variety of projectiles and powers, practical. Typical (modern) .22 PCPs will shoot in the 30 to 45 fpe range making them suitable for dispatching critters up to groundhog size and even raccoons with a well placed shot.
The .25 is a bit heavier in cost and power making it more suitable for larger pests (raccoons and porcupines) but not as practical if you like to do a lot of plinking or target shooting. It's good if you are primarily into hunting but may be a bit over powerd for squirrels and rabbits.
The larger calibers are best for long range shooting (less wind drift) or larger game. Cost of ammo and air are not much of a concern when hunting but may limit the amount of plinking and target shooting you will do. High power (and noise - I'm in Canada as well so moderators are verboden) might be an issue.
Hope this helps reduce the amount of airguns you have consider.
Oh, if you were asking for a recommendation... I have a good variety of PCPs (Air Arms, Benjamin, Feinwerkbau, Walther, Weihrauch and FX) and for my interests (plinking, target shooting, pesting and some squirrel hunting) a .22 caliber 600 mm barreled FX Crown Mk2 is my all around favorite.
That being said, there's no one perfect airgun that does everything. Your first one should meet your primary needs. Once you find what you like, getting the second one will be easier!
Good luck!