Not sure how advance my duskblade/archivist

I have a 3rd level elf fighter with 15 str, 14, dex, 10 cons, 13 int, 11 wis, and 14 cha. Now im about to level up into archivist and increase my int as my ability point. But what i want to do is train out my fighter levels for duskblade and advance as a duskblade/archivist. But if i do that im not sure what to shoot for for each class im really tempted to go for 9 duskblade/11 archivist so i can be able to channel both vampiric touch and harm but im not sure. Also this campaign will most likely end somewhere around lvl 15-20. any idea on how to build my character or tips on what to do would be very helpfull.

You might want to repost this into the rules forum, rather than the conversions subforum.