It all depends on what you want to achieve with 2 options that will influence the way you shoot : handheld or tripod.
Tripod you can use any format and camera but you loose the instant snapshot you may want.

Handheld options are various.
Box cameras with lens on hyperfocal. You are limited by the need of light to close down the aperture or you use flash (a strong one...)
I used to shoot in Paris with a Hobo style 8x10 and had an assistant holding a Norman flash...
Not really discret. A real pain in fact !

The best option is the good old Graflex SLR. I got one recently and it's a joy to use handheld.

Whatever you choose, you need to make it yours and make it work. Camera becomes your hand and you forget about it to concentrate on the subject,
Easier in 4x5 than 8x10 for street photography. In the end you will have to compromise as for DOF, speed, etc...
And for enlargement as John said there is no issue at all.