I think the Titan series has a lot of potential to tell really different kinds of Trek stories. At the moment, the 24th century seems largely focused on the Typhon Pact. VOY is off doing its own thing, of course, but the TNG/DS9 stories seem very much geared towards pushing the conflict with the TP. Titan's most recent entries have also dealt with the TP but the premise of the series should allow it to go off and explore strange new worlds (as the earlier novels did).
I like the Titan's crew. Clearly the most diverse, as it was intended to be. I think the reason I keep reading the series is that I enjoy the characters. The actual novels, themselves, have been of a mixed quality. My favorites are
Taking Wing and
Sword of Damocles (I also really enjoyed the Titan's participation from the
Destiny trilogy). The last several Titan novels (
Over a Torrent Sea,
Synthesis,
Seize the Fire and
Fallen Gods) have been less enjoyable.