I have taken a break from frequent flying due to professional reasons, and I have not been active on this forum for a long while.

It seems that I might be able to get back into the game of very frequent flying soon. There might be some people here who like a challenge and can give me some useful advice.

Background: I have done a decade or so of pretty frequent flying and statuses until early last year. I was based in Germany, until early 2012 with heavy intercontinental travel (about 40% paid C, rest in Y with as many upgrades as possible). FF status:

AA: EXPLAT 2001-2012, now lifetime platinum with >3m miles.
LH: SEN 2006-2014
AFKL: I had a status match into Plat, but never used their services and status expired.

Early 2012 I got a new job and was really low on flying, only some few short trips in Y within Europe.

Looks as if I might move to MEX now, with a lot of lying to do:
- very frequent within Mexico (C and Y)
- very frequent between Mexico and Central America (C)
- some flights to North and South America (C)
- maybe 1-2 times to other continents (C)
- 4 times per year private to Europe (Y with upgrade, miles, maybe 1-2x paid C)

Question is, what would be my best option for FF?
1. Try to renovate SEN at LH?
2. Make the best out of PLAT at AA and maybe try to get back to EXPLAT?
3. Switch to Skyteam, given that Aeromexico is the only full service carrier out of MEX?
- 3a. AM FF program?
- 3b. Delta, maybe try to statusmatch?
- 3c. AF/KL?

What do I value most about FF programs? Good comfort on (private) intercontinental flights for reasonable prices (by upgrades or lowly priced C class), reasonable connections on business trips, possibility of lifetime status.