I think that depends what you mean practical travelling distance at the end of the day, if it's not somewhere you can reach at the end of a night out (3am or so) then you do definitely risk not integrating, beyond that - it doesn't matter much how many people live in the same halls as yourself.
You'll (hopefully) befriend your flatmates and maybe a few other flats but pre-dominantly your friends are going to be on your course, people that chose to study the same thing as you are far more likely to relate to you. I've practically lived in several friends flats at points in my uni life. So my advice is to take that out of the equation.
Now a lot has changed since my first year (Courthouse was owned by Abertay back then) but generally speaking you'll get what you pay for, in terms of proximity it's roughly: Meadowside, Courthouse, Victoria Chambers, Old Mill, Opal, The Hub which are all within 5 mins walk anyway then Lyon St, Alloway.
Facilities are best in Opal & The Hub - with the price tag to go with - Old Mill is pretty decent, Meadowside, Alloway are reasonable
The rest I have no knowledge of.
Experience, well I didn't live in any of these halls, my halls have shut down but the general rule here is, the cheaper the halls the better the experience: Alloway I've heard some ridiculous stories about, if anything it sounds hard to buckle down some times. Whereas Opal will keep you on quite a tight leash, lest you break anything valuable. Personally my halls were pretty terrible, prison styled, cold brick walls and a separate building to wash your clothes but it led to some brilliant times.