Yes, many Forum members are very conscious of how their set-ups interact with their environments (which includes house construction), and one of the fundamental learnings of this mad hobby is that simply spending more £/$ on kit can mean that the quality of replay goes backwards not forwards e.g. an amplifier which delivers much more bottom-end bass, can create material issues in a room, with boom and in setting off resonant frequencies. Generally, the sturdier the construction of a building the better e.g. concrete block walls.
The trinity of the environment/amplifier/loudspeakers can be a challenging puzzle to solve.
And, as @Innocent_Bystander highlights, these things are wholly subjective (your ears alone) and there are so many variables to consider.
See here for some examples:
The Listening Room Reality - Hi-Fi Corner - Naim Audio - Community
All you can do is engage with people (dealers) who are prepared to give you the most help, which is what you are doing.
There is no yes/no answer as to whether you will like a REL and an educated dealer may suggest other speaker alternatives at the same overall price-point. Of course, going to a dealer and listening to some speakers at the outset should assist in filtering-out some which don’t suit your tastes.
Lastly, the real key in all this is where you sit and the kit is placed in your 35’ x 12’ room. If playing down the length and being far away then you risk getting lots of reflections from the walls (and ceiling) which could (materially) degrade the sound. Akin to photography, there are focal points in a room for speaker set-up and listening position.