I'm just delighted that Lucky is coming second so far - I was expecting the Galliano's Circus books to be less well known and popular than some of the other series. Also, Lucky's "too good to be true" cleverness that I mentioned before was something I thought might put people off voting for her, plus the fact that unlike Timmy, she's not involved in any really dangerous adventures or mysteries.
I wouldn't say Timmy is "less developed" than Enid's other dog characters - I'd say he's significantly more developed than Buster, and probably than Scamper (though I'm not well read when it comes to the Secret Seven books, so can't judge very well there). Both Buster and Scamper are adjuncts or sidekicks to the group of children in their respective books - the Five Find-Outers
and Dog, the Secret Seven (of whom Scamper isn't one). Timmy, on the other hand, is actually one of the Famous Five himself - he's so much a part of the group, and so vital to all their adventures, that he's essentially ranked equally with the four human members! In fact, he's always been my favourite of the Five - I would never have particularly wanted to meet Julian, Dick, George or Anne in real life, but I wouldn't have minded a dog as loyal, courageous, intelligent, devoted, and downright fun as Timmy.