We do have more than a handful of maps now, with only one we groan about when it comes up. Gameplay has changed a lot as far as builds used, they have added a skirmish mode, which is straight up last team standing. They have greatly improved assault to give the bases significant defenses, eliminating the light mech cap rush, except as a dedicated effort. There is no shortage of mechs to play around with, even before the clans dropped.
The game itself is still your usual round-based conflict, with no greater meaning other than accumulating money, XP, building your fleet of mechs...and sharpening your skills. The difficulty level has risen significantly from the beta days, since with the current set up, everyone is just constantly sharpening their skills without having to think about a grander scale war.
All of that said, it's still a lot of fun.
I wouldn't buy a package, especially since now you can play with the builds on smurfy: http://mwo.smurfy-net.de
You can still buy individual mechs a la carte, which gives you 3 variants for leveling up. http://mwomercs.com/clans
The Thor collection might be a good deal though, and cheaper than buying 2 a la carte--if you like lighter mechs. Also has 30 days of premium time to get you going on your funds again and getting XP for these new mechs.
They aren't snake oil, and this is a better release than the phoenix mechs. They did an excellent job balancing with the IS mechs with the built-in tradeoffs, but there is a definite difference to be seen.
IMO, get the Timberwolf and a Stalker Misery. Best mechs in the game IMO.