Coupla things I look for in .22LR ammo: how's the accuracy & how's the price.
For almost any .22LR applications, any ol' (but accurate) loading will work quite well if you put the bullet where it's supposed to go, & no real need for any HPs neither.
Depending on what you'd call a "varmit," may just be that it's too big for a .22LR anyway & no amount of "specialty ammo" will make up for the "lack." Some things a .22LR wasn't meant to do.
No flames, etc. intended. I just see some hype sometimes that tries to make a .22LR into something it isn't.