15 posts to PM is too many
Got here and posted a thread about DPF/EGR delete - a member PMed me and I can't even respond. It's pretty awful, and a bad user experience for someone who would actually like to use the forum right off the bat. Especially given a forum that's so small in user-base size.
I can understand the no links/URLs for 5 posts (however I think QUOTING a link or URL should be allowed - that's another annoying experience I had already) but 15 for a PM is too much, drop it to 5. Most spammers will be found before 5 posts and banned if you have proper admin/moderator support.