Greeting fellow former fish freak!

I too am sticking my toes into the herp hobby. Just got out of the aquatic swimming pool not too long ago.
Ah yes- a riparium is probably more up your alley.
bristlenose pleco will do fine in a 29gal. Have you considered corydoras sp? There are hundreds of different color variations (my favorite being C. pygmaeus. and C. trilineatus which is often dubed the "false julii" corydoras.) If you are not familiar with these guys, I'd like to hit your curiousity button and encourage you to look into them!
Newts would fare well with bristlenose pleco, dwarf gourami, and corydoras. They'll eat what they can put in their tiny mouths, so don't expect any surprise gourami or corydoras fry to survive. I would also suggest small tree frogs like a gray tree frog or something similar that is not against your state/country/whatever-your-local-government's laws. A simple google search should give you a list of what you cannot keep as a pet. spring peepers are also nice I've heard (going to test the theory out this coming spring).
Perhaps a common house gecko? I am not sure if they require UV lighting... It would be simplier if you did not have to offer UV lighting, but it's not so much of a trouble to do so.