I would say go for the biggest as possible, the type of sound will be the same in every aspect on all Genelecs, the difference is the SPL, the headroom, the dinamics, ..., based on the room size, but the Genelec taste will be there on all models.
I had last week the 1036 playing at reference level with a Datasat pream in a 100sqm room and WOW ! Front row of Madonna, Sting and DJ Tiesto at incredible sound presure and no distorsion or compression or clipping. Same on movies.
Regarding the HT and PRO models they are the same.
All 3 way models can offer good performance on a mid distance, similar to a traditional 2 ch stereo speaker, I have compared them to many well know products and ussually they beat them all in dynamics at half the price.
Of course Genelec is not for all type of customers, if they listen to classical music, they will not liked it, basically because when they listen to a speaker designed for been flat 20 Hz to 20 kHz with no limitations they will feel it is agressive on the highs and vague on the bottom lows. Seat in front of a violin or a trumpet and then play the same on the Genelecs and you will understand why most recording and post production sound engineers likes Genelec, because it tells you what you are listening and doing, the reality of the music.
Audiophiles look for a particular type of sound they prefer ( colorated ), sound engineers look for the true, that is why there are a few Pro speaker brands and hundreds of Consumer brands. Pro stuff use to be EQ and used in controlled rooms, with acoustic design and treatment. Consumer models are for the living room, so the designers tunes them ( EQ ) in the croosover, and we with the cables, the electronics, the placing, ...
For the rears you can go for the 2 way models, no need for more. The Datasat gives you information about channel levels in real time and none of the disc played had the energy of the front channels, so if surround music is not the most important use, 2 way small monitors are fine, or the 1038 the smallest 3 way.
A good idea is to place power amps near the speakers with just one meter of speaker cable and run long balanced audio cables.
Better if you stack the fronts in the wall, on high and tillting down.
Good luck !!!