I fly United Express with some regularity (much to my continuing dismay). There are many operators (GoJet, Mesa, Trans State Airlines, etc) and some are better than others.

You were most likely on an Embraer 145, if the seats in the whole plane were in a 1-2 configuration. Unless this was a weird exception, the CR7 is 1-2 in First Class and 2-2 in economy.....

I have not yet seen a sign that a sink is permanently disabled, though I have had many United Express flights were the sink just doesn't work and the towelettes are used instead.

I try to avoid any United Express flights, but it seems United continues to expand their use for anything except major routes. There are some United Express flights which are 3 hours in length now...kinda stretches the meaning of the term "Regional Jet" when they are on these routes.