Tamers just feels like the strongest series to me, its first half is purely character development and then the second half dives right into this pretty dramatic story for the rest of its run. It even becomes the one series so popular with older viewers that it got a spinoff novel made for adults.
What I enjoy so much about Digimon's first three years is that there's a clear progression of fun and adventure to that mixed with drama, to a ton of drama, it feels like a stylistic maturation, and that's the sort of thing I love. And I still really love Frontier, but I'll fully admit that it leaves...a lot to be desired - which can also be said for Savers and Xros Wars, especially Xros Wars.
I've never been a big fan of the Digimon games, though re:Digitize does look pretty interesting, as does the new upcoming Adventure game. But I think I'm now always just going to want an anime in the style of the re:Digitize game, that opening sequence is not enough!
I put it that way because the movie + first two seasons was the 'Golden Age' of Digimon for me. I liked Tamers, but by then Digimon was falling out of favor with me just a bit. And yeah, I've got the nostalgia goggles on hard for the first two Digimon seasons, haha. Spent many a Saturday watching those shows.