I'm sure you'll get references to using the 452 Varmint instead of the Silhouette, so let's go ahead and get the differences in the models of 452 out of the way here. The CZ 452 models are one of the most often seen rifles used by mid-range shooters in smallbore silhouette. There isn't a 452 model that's really well suited to silhouette shooting, though. The Silhouette and Style (just the Silhouette with nickel-plated action/barrel) have a stock that's fairly well designed for offhand shooting, but they are very light, which isn't great for slowing down the wiggle and getting on target long enough to get the trigger to break. The Varmint model has a heavier barrel and overall heavier gun weight that helps slow down the wiggle, but the stock is designed to be shot off rests so the wide foreend and sloping pistol grip doesn't work as well for offhand shooting. The American is the only 452 model in 22lr that has two action screws, which is better for overall accuracy and is the way an accurate bolt gun should be designed, but it doesn't have the heavier barrel of the Varmint that helps slow the wiggles or the offhand stock of the Silhouette/Style, so it's really the last choice when it comes to a gun purchased specifically for silhouette shooting. If CZ would make a model of the 452 with the Slhouette stock design with two-action screws like the American and the heavy barrel of the Varmint, they'd pretty much take over the low and mid-range smallbore silhouette market. Until they do that, though, you have to choose which feature you want most and buy the model that has it.
As for making the CZ 452 better, there are lots of things that can help. The CZ 452's biggest problem is its trigger design, and since the trigger is one of the most important aspects of a silhouette rifle, that should be taken care of first. The first modification that will be recommended, and the one you can skip if you are accustomed to higher-end rifles like Anschutz, is the kit of springs and spacers from Eric Brooks. It does help the CZ's trigger a lot and will make the CZ much better for casual shooting, but it's not nearly enough to make it a competitive silhouette gun. Go ahead and step up to the Automated Solutions adjustable sear. If there is only one think you do for a CZ, that should be it. It will take the decent trigger of the CZ and make it into a good trigger. It will be $60 or so well spent. Getting rid of overtravel in the CZ's trigger is a lot trickier, though, and not really something that needs to be covered here. After you get the trigger fixed, you can do all the usual accurizing tricks like bedding the action, floating the barrel, etc. You can make most any CZ 452 shoot groups of half an inch or a bit better at 50yds. Getting much better than that on a consistent basis can take a lot of work, though.
I've been shooting my CZ 452 Varmint for both hunter and standard class in silhouette for quite a while now. The trigger kit from Eric Brooks helped some, and the adjustable sear helped a lot more. I have one of the Silhouette stocks on the way to me now and I'm going to open the barrel channel up to fit the heavier barrel so that I can have the best points of the Varmint and the Silhouette. Even with doing that and countless hours of accurizing work, the gun really won't be anywhere in the league of an Anschutz 1712 or similar high-end guns. I wish it weren't true, but it most definitely is. I'm just trying to make my little CZ be a little better while I save up for an Anschutz 1712 or build up a custom hunter gun myself.
Honestly, my advice to you is to forget the CZ and go ahead and get the Anschutz 1712. If that would make money tight, it would be better to sell the Anschutz 1710 and get a good gun and good scope for hunter class and just use it for standard class, too.
