I have three forums myself which incorporate SMF with Tiny Portal, I'm a cheapskate (GNU=free) and I have had that problem a few weeks ago. The genealogy forum was up to almost 700 members but every other member was a spammer. I changed over to SMF and did not move nor convert the database. I did not think about the locking of the thread until a certain number of posts, I'll have to check and see if SMF has that function but I'm sure it does.
I guess another way to do it is to make groups and a certain number of posts allow a group to view certain threads, when a member reachs that number they can view and post. Close to what your talking about I think.
You do not have to worry about me posting ads or whatever, I have been totally swamped for 4 months now and it is a one man operation. I have hosted for a little while now (10 months I guess) and have 26 domains on my server. Thanks for the explanation and it makes good sense.
