Those two are so vastly different I dont think theres any real way to guess.   Heres what I will say on the matter ...

I ... meaning me and me alone ... would choose tabla for myself, because I like and play arabic/indian music and not latin, but timbale for your wife.

The timbale would fit in better with her current collection because of the latin/afro-cuban angle.

Tabla will pretty much definitely require an instructor, even with a prior knowledge of hand drumming (this is coming from the patron saint of self teaching on this forum) while timbale can be a bit easier to get a handle on.  

ONLY get her tablas if you can locate a qualified local teacher, and maybe buy her a lesson or two as part of the gift. Unlike most drums, they are NOT an instrument that you can just "wing it" with. If you do that, get the tabla teacher to help you pick out a decent pair for her.

Timbales are a safer bet, if she's expressed an interest in them.

I agree with Mr. A ... tabla is probably the most difficult percussion instrument on the planet (in my opinion). If she's not serious about learning even the basics ... the instrument will end up being a nice conversation piece in your living room.

Timbales would be something that she could use in a wide variety of music genres, and can be used in both a drumkit or percussion set-up. I'd go with the timbales.

One final note ... it's very easy to buy cheap quality tabla, and they don't sound very good. With timbales, it's almost impossible to lose, although there are varying qualities out there. Unless you are prepared to really get a nice set of tabla, again, I'd go with the timbales.