Your convertors (001 & Alesis AI-3) are a weak link as well... maybe upgrade them to a 002 indeed if you want ProTools LE (no need to run at 96khz tho). Or pick up one of the RME boxes is you can do without ProTools LE.
Don't get the Behringer mixer anyway

You're better of mixing inside the computer then.
The LA-610 was discussed in a few threads a while ago. Try a search.