30 to 40 recips ....damn...lol...thats more work than building the site itself! Anyways, here is one suggestion: With your mirrors and recips, try to balance and spread out an even mix of big LLs and directories with the smaller ones. Example: You have 12 big LLs..and you make 4 mirrors and plan to put 6 recips on each. Put 3 bigger recips with 3 smaller ones on each one. Reason --> it builds a good network of traffic with everyone (including yourself), it helps build up the smaller guys which in-turn will benefit you over time, plus several more benefits. In a nutshell, you want to maximize your traffic across "ALL" of your mirrors. Just don't go crazy with mirrors, and as for recips, I personally think a max of 12 (or less) is good per mirror unless you are using only text links (not text banners).
Don't forget to do some search engine optimization as well...you will thank yourself later for this.
