I'm a huge fan of the 357 magnum both as a target/plinking round and a hunting round (given its range limitations). If you are a reloader, you can taylor your rounds to improve carbine performance... in particular, Lil'Gun can turn out some excellent numbers for the 158gr JSP and heavier cast.
As to the baby rolling block, I used to own one of the early Uberti/Navy Arms imports and liked it very much. It is an extremely nimble rifle with the 18" barrel. I ended up selling it when I came across a well-priced Marlin 1894c. For me, the Marlin is more flexible and a bit more fun at the range.
One of the things that you could look into for the RB is having the chamber reamed out to 357 Maximum. There are a couple posts on the Internet that describe this rechambering. The SAAMI max pressure for 357 Magnum is 35KPSI while 357 Maximum is 40KPSI, so there is a difference and it's worth getting a competent gunsmith to determine whether your particular action is safe to make the conversion with.
The 357 Mag is a capable round, but if you wanted to give it a bit more oomph, the 357 Max can approach 35 Rem performance. At that point, I'd think the limiting factor to effective range would be the quality of sights on the rolling block. My RB had a leaf rear and no provision for a peep, which is one of the reasons I sold it... I didn't want to drill/tap it.