...........finding the ammunition your rifle likes...........
I think that IS the "hard and fast rule" for 22 rifles and pistols.
I've been lucky that the most available and cheapest stuff hot well in all my 22s. Almost all have been Rugers, except for a couple CZs.
To quantify what I consider "accurate" in my guns, I'm not talking about groups in the "tens," like guys on Rimfire Central, I'm talking half-inch five-shot groups at fifty yards with a rifle and one-inch groups from a pistol at twenty five yards - on demand, not on occasion. That's not that great by some standards, but it is perfectly adequate "hunting accuracy," which gets me to 75 and 80 yards, with a rifle, to handle pesky starlings.
That may narrow things down a bit, or more so - widen them out, depending on how one views it, giving one a wider selection possibly, of some of the more cost-effective ammo. Functioning is also as important as accuracy, and whether the ammo makes a mess of your bore is as well. LIke I said - I got lucky.
I believe a body could do no better for effectiveness on game than to implement one of the nose-altering 22 setups. Buy the ammo that shoots to your standards, regardless of the nose, and then make the nose work the way it needs to. It may be slow, but I can shoot unmodified ammo with impunity and switch to modified noses for when it counts without any adverse reactions regarding accuracy or feeding.
I am certain that the CZs I've owned would shoot better than a half-inch at fifty, if I'd been more selective in ammo, but I never saw the need if I could shoot a squirrel head at fifty yards with what I had. But, again, that's the standard I personally applied and others will have more stringent standards, and some less.
I know I'm just grousing again, but it would be nice if "standard velocity" really were the STANDARD these days. The only fault I find with the cheap Federal "Value Pack" ammo I have is that it is too LOUD. I'm not sure it makes a big difference in effectiveness on game/vermin/varmints having the extra velocity at what I consider (personally) "reasonable ranges" for the 22 LR, and I am absolutely certain that it does not make punching through paper or cardboard any better.