I was in Seminar last year and a few years ago a sis was there too. This year I have two pretty close friends who are there so I have some perspective on it.
Dress code – not too restrictive. the usual button-down etc.
Yeshivish – I think a lot of sems are good so I’m not gonna compare one to the next but it’s a very normal place. Girls are solid frum and aren’t into bad things at all. some would be called yeshivish and others would be more balabatish but not bummy.
Warm – You betcha. Doesn’t matter how many girls there are because they are so serious about being there for the girls and they really are. the staff is there for them and had them over at their houses and makes real time for them. To me – that and the upbeat atmosphere was what made my year so awesome.
rooms – some have 3, some 4, 5 and some 6. it’s not cramped but it’s not super roomy. i heard they added a bunch of showers this summer so now there’s a ton of them.
The two best parts about Seminar is their staff and the girls. i loved ’em both and so did my sis.