Been flying around for the past one year. Saw the movie "Up in the Air" and dived into this FFP world😅.
Domestic:
I have been redeeming all my FSC flights to United Mileageplus (love the fact miles never expire). Will keep doing that until Tatas figure out what they want. For nearly all other instances I use AIX (neupass). I enjoy their free privileges (separate check in queue, first to board, priority baggage) a lot, and redemptions are cakewalk.
International:
Haven't explored outside India yet. Aeroplan seems nice, considering the number of partners they have. Otherwise United's always there (zeroed out Delta Skymiles to be best for Skyteam, Qatar Privilege Club for Oneworld, suggestions welcome).
PS: Haven't redeemed flights so far on United, but despite all hiccups it seems good and overall reliable.