No matter what format you get..5x7 or 8x10…you will eventually want to enlarge. When that time comes, you could trade the Beseler 23C for a Beseler 45, with the 8x10 conversion. Then you would still have only one enlarger. And at current prices for enlargers, it wouldn’t be that expensive.
But for now, if you want contacts, I’d go for the 8x10 camera. 5x7 contacts are just too small.
I also have the Wehman 8x10, and I put it in the f64 8x10 bag along with two lenses, 5 filmholders, lightmeter, loupe and darkcloth. I have done a couple of 2-3 hours walks with this setup and it`s no problem at all, the f64 fits me wery good, and I`m a small guy, 166 centimeters....
I have an SV45U, and yes I miss the asymmetric swing and tilt on the rear. I had one, but I found that because of the design the camera was unusably stiff when you tilted it over and tried to use the asymmetric swing - it would rotate the camera on a Ries A100 rather than swing, and others have noted this too. So I ended up with a mint SV810 with 5x7 and 4x5 backs i found on eBay at a nice price.