Oh goodness what I wouldn't give for Riko and Haru to NOT end up together! Seriously, can't we just have two main characters in a Yuri manga who don't end up together? 'Specially considering Riku have Akane around to fill the void in her heart... and stuff.
Besides, I feel some of the Riko-Haru Owarai-magic would disappear should the two get in an actual relationship. They make such a great boke-tsukkomi pair that I would be saddened should this disappear, romance or not.