I'm sure there's a way to avoid the SPs to obtain the Next IDs, but here's a possible suggestion.
I can't assure it will work, but it can give you an idea.
--Removed
EDIT: There was an unneeded SELECT
Luis C.
General Disclaimer:
Are you seriously taking the advice and code from someone from the internet without testing it? Do you at least understand it? Or can it easily kill your server?
How to post data/code on a forum to get the best help: Option 1 / Option 2