Many good choices. I cannot recommend what is "best".
I like my CZ 455 Lux which I use for grouse hunting, scoped with a Leupold rimfire 3-9 scope. Birds on the ground, head and neck shots only, so I miss alot, but plenty of birds where I go. Although a 2-7 or 1-4 scope might be better, since sometimes the 3x magnification is hard to find the birds with, which are almost always well within 20 yards. I use an instant adjustable sling and use the hasty sling method for shooting.
I really like the safety on the 455 and 452 models, because its very tight and hard to switch unless you really want it to. I have to punch through thick bush going after birds, with sticks sliding across me and the rifle, and just changing the rifle from shoulder to shoulder and different carries throughout the day as it drags across my clothing, I know that safety catch is unlikely to be accidently knocked into fire position. That said, unless I am chasing a bird that I can see, I always carry it with the chamber empty and cycle the bolt when I need a round. I use the 5-round mags.
I have not seen or handled the new CZ 457 models, but they changed the safety design to a simple forward/backward North American style, which looks to me to be less resistant to being accidently switched....but I have never handled one so can't say with any authority.
CZ changes the barrel length of the various Lux models. My 452 Lux has a 24 inch barrel (rather long and awkward for thick bush), and my 455 Lux has a 20 inch barrel which is better for the hunting I do. I could easily like an 18 inch barrel since I use a scope and the sight radius is not an issue with the scope. For iron sights if you were to want those, the longer sight radius is more accurate, so if you are planning on using iron sights, think about the ability to mount a rear peep sight which is a better option than the factory barrel mounted rear sight IMO.
Photo below of my CZ 455 with Leupold 3-9 scope and adjustable sliding sling.
The semi-auto option is probably a better meat getter. There are many grouse I miss as I am cycling the bolt and re-establishing sight picture for the 2nd shot when, with a semi-auto I could have stayed cheek down on the rifle and maintained sight picture in the scope for the follow-up shots. Grouse are usually moving when I shoot, so I miss alot. Rabbits might be more forgiving for a manual action since they tend to use the strategy of freezing in position.
Good luck in your search, and happy hunting!