This looks like an interesting thread. I have life changes coming up soon, I'll explain:

Currently:
Live and work: TLV
Family: London (LHR et al)
Work satellite office: SEA
Work owners: LAX

Hoping to move to the US next year, so could look like;
Live and work: SEA or SFO
Family: London (LHR et al)
Work satellite office: SEA
Work owners: LAX

(1) What is most important to you in a FFP?

Lounge access, priority security, upgrades in seats / class.

(2) How many miles do you usually fly each year & in what class? How many flights/sectors?

It varies. Assuming there are not too many COVID variants, I might fly TLV-LHR ~3 times a year, TLV-SEA 1-2 times and TLV-LAX 1-2 times. So we can say maybe 40,000 plus minus.

(3) What types of fares do you usually buy?

If I'm paying Economy or occasionally Premium. If work is paying, Business.

(4) Can you choose your airlines and/or class of service? Do you travel for work and/or pleasure?

I can choose airlines, class as above. I travel for work and pleasure as above. Presumably if I move to the US I'll do more of my pleasure travel within the US.

(5) Which routes and airlines do you fly most often?

See (2) and (8).

(6) What is your home airport?

Currently TLV, next year probably SEA or SFO.

(7) Do you have FFP status of any kind in OW or other airline? What is it? Do you have any miles banked in a FFP?

Mostly American, hoping to save Platinum through 2023 (see thread on the subject). 59,205 award miles.
Also BA Bronze with ~16,000 Avios, Virgin Red with ~14,000 points.

(8) Preferred Airlines? Most common Airlines flown on?

I like Virgin, Swiss, Lufthansa, but they don't often suit my routes so I usually find myself flying American / BA, and I'm generally okay with them.

What does the font of all knowledge think?