I have gone to two concerts at the Fillmore and loved them.
First I'm on the taller side, and in heels I'm about 5'10+ so there is really no bad place for me to stand. When I went to the 3EB concert I went with my friend who is a whopping 4'10, everyone there was so nice and friendly they let us get to the front so she would be able to see and let me stand at the end to not block views.
The 3EB concert I noticed the security because we were in the front row, when I was there for Gavin DeGraw the only time I realized they were around was when I was getting the pat down coming in. I think that was the most action I saw that week ;)
As for the drinks, it's what's expected at a concert place. It's easy to forget because of how intimate it is. Yeah bottles of water are $4, my double vodka tonic was $16, if I didn't like the prices I don't have to drink (but whats the fun in that).
I will continue to go to the Fillmore for concerts, I think it's a great place. But I will continue to wear heels when I go to get perfect views.