Of course it can be modded!
In fact I hope that as RUb versions stabilize (and I would in fact seriously expect a final RUb version from Beery sometime in the not-too-distant future), RUb itself becomes a base for further development. And there's definitely a lot of stuff that can be altered.
For instance, although my setup right now is technically an early RUb 1.43 beta, it's so heavily modded that it's unrecognizeable in some areas, while in other areas it's already halfway to RUb 1.44
