I dislike Betazoid telepathy (I'm more of a Babylon 5 or Miranda Jones style telepathy fan). Deltan abilities are wonderfully nebulous and wider ranging:
Their pheromones arouse some other races, can dull pain, and they are empathic. Seems to me that their schtick revolves around an olfactory sensitivity and generating their own pheromones to influence those around them. How is that not more interesting than, 'He's hiding something Captain' or making Troi wholly absent sincve her abilities would bust the mystery plot wide open?
Deltans are partially telepathic too, forging telepathic bonds with lovers and family members that can span considerable distances. They can project images into each others' minds.
What can we say about Betazoid society after 20 years of TNG? Almost nothing that makes us want to know more. Deltan society on the other hand remains intriguing and teases us with the prospect of an erotic paradise. Such fun.
I may be biased because I was very fond of Zinaida in the TWoK novelisation. I was very disappointed that the recent comic adaptation didn't borrow more elements about Peter and the scientists. Compare Zinaida to Troi, I know which one I'd rather have as a recurring character.
BTW - I love Troi - she was just a character who was too much of an afterthought for too long because betazoids were so poorly realised as a species.