(1) What is your home airport?
LHR
(2) What types of fares do you usually buy ?
Premium eco (long haul), eco (short haul)
(3) How many miles do you usually fly each year? (<25K, 25k-50k, >50k)
1 transatlantic and 1 european roundtrip per month, ie 7000 and 1000 per month, so about 90k/year
(4) Do you have any kind of status at present? What is it? (UA Premier, M&M Senator etc)
BA Silver
LH FFT
(5) What is most important to you in a FFP? (Frequent upgrades on travel, priority services when flying the airline, good award redemption rates, free lounge access, etc.)
Priorities, lounge
(6) Which routes do you fly most often (US Domestic, Transpacific etc)
LHR-US, LHR-Europe
(7) Preferred Airlines
For *A, SK, LH, UA for domestic US
(8) Do you travel for work or pleasure? (Can you chooose your airlines, class of service?)
Work, I choose airlines

As I am reaching FFT in M&M with 35KMiles, I will be star silver, which is quite nothing, except at LH (lounge). I would like to aim for star gold, but M&M requires 100KMiles, I won't make it.
I recently saw that for UA, silver is 30KMiles and gold is 50KMiles. If I take as an example my last trips,
- 1 transatlantic in Premium Eco on SK got me 1.5x miles, ie about 6000 M&M miles. When I look at MileagePlus, it is also 1.5x for qualification -> same
- 1 european in Premium Eco on SK got me 1250 M&M miles. MileagePlus would do 150%, ie about 900 -> less
- 1 european in eco on LO got me between 200 and 1000 M&M miles, MileagePlus would be between 25 and 100% -> a bit less
- 1 domestic US got me 100% -> same
- TAP european, etc, seems to be the same.

It seems that I may gain a bit less miles on UA, but the silver threshold is also a bit less than LH; however, the gold threshold is half lower! I'm therefore considering starting crediting my miles to UA. I would have no issue to make the four segments. Anything missing?

I am a BA CE member and my membership from Jan 2017 will be valid till Jan 2019. Is it the same for UA and LH?

I'm also considering SK Eurobonus or TP Victoria, possibly AC, but for other *A airlines, I don't see myself flying on them often

Thanks,