I've dabbled....
The problem with making older cards is finding photos and turning them into color paintings. Notice the Williams. It's not just a color photo but an actual aritistic (although crude) looking painting. Photoshop has some options, like the watercolor effect, but it's a bite to get it to look right. I rarely do. I think the only way Topps could get it right would be to hire actual artists - it's really tough to recreate a 1953 looking card with just photoshop.
The next issue is the font used on the older cards. I always have to find something close and try to shrink the text or expand it to get it to look right. I rarely do! And I'd add that colorizing a black and white photo to use is also a real pain.
And as for the backs: I'll leave that to the retirees with way more time to dabble than I have. Once you try it, you really appreciate the time and skill Mr. Lemke has in making his cards. I recreated the back of a 1976 Mark Fidrych card and it took me forever! It's a great stress-reducing activity for me though, so I just have fun with it. I like to call it Phun with Photoshop!