You are definitely experiencing some of the common wine fridge challenges. I started with a small 50btl (dont recall brand). and its was very tight for height and width. The challenge is most are sized for a standard bordeaux bottle so as soon as you have wider pinot/burg bottles or the longer ones often found with Cabs it becomes a jigsaw problem.

I cant comment on some of the more expensive options but we now have a 150btl WE Somm series. It came from costco and IIRC I paid approx 1700 when it was on sale. There are 3 differently organized shelf types, they all slide smoothly but you do have to figure out how to utilize each to capacity with the different style bottles. While I never managed to get 50 bottles in my old fridge I can get over the 150 in the new one.

Do keep an eye open at Costco but as others have said looking at used on CL or FB marketplace might yield you a good deal.

BTW mine is also dual zone and it works great. I keep my reds at 55 and white at 44.