I do not understand what you mean by AI? I have been to a lot of resorts in The Maldives and Bolisfushi is the resort of choice for a lot of Heads of States or top foreign dignitaries who visit Maldives. They are not just marketed like the International Chains simply because I think they do not need to.
Maadhoo is a small island with top quality. I guess it depends on the personal preference.

Sorry to be not precise enough, AI = All Inclusive. I avoid such hotels simply because I don't drink at all or eat much.

I would add JA Manafaru to this list. The previous management team from Amilla have moved over so the food and service are great. It is quite remote - the most northerly you can go - but it makes for a beautiful and tranquil stay. Stunning beaches, unique wine cellar for private dining, ex-Waldorf Astoria so quality rooms with nice private pools.

Similar to OP, travelling with young (and old) so avoiding overwater accomodation.

which would be a good taster for first time at Maldvies ? Only planing for 3 or 4 nights in Feb 2025.

all inclusive would be prefered

What kind of resort? Do you want a boat transfer or a seaplane transfer? Single bungalows or two stories?

Seaplane transfer would be preferable to get it ticked off a Maldives experince.

I've been looking and would there be a winner between these 3 ?

Sun Siyam Iru Fushi
LUX* South Ari Atoll

Angsana Velavaru (cheapest by almost half !)

Never been to LUX, but between Velavaru and Irufushi, Irufushi is much better. Yes the seaplane flight is an experience if you have never traveled in a seaplane. But I would say that Irufushi would be better than LUX too.