Romuel, depending on your level of skill, I see that as less of a problem than 'too easy' a uke. Properly done, a technique should work (ikkyo, for instance) whether or not uke chooses to go along - in the long run, your aikido may become more effective with a resisting uke.
My own uke difficulties have elements of both too easy and too hard: The only guy in the dojo that's newer than me.
He's coming along very well, but his one main difficulty is he wants to try too hard as uke - instead of being led through the technique, just holding on to nage's wrist in kokyunage, for instance, he takes the initiative, moving himself into what he thinks is coming next. Since he has only a tenuous grasp of what's coming next anyway, he's liable to go wiggling off in one of a hundred completely unexpected directions - it's hilarious to watch.
Still, it helps, in an oddball fashion. I was practicing ikkyo-irimi on him, and the second I moved to rotate the arm, he twisted away in what he thought was the right direction. I continued with the technique anyway, (slowly, to avoid accidentally hurting him) modifying the line of force to compensate for his movement. The technique worked well; he went down on the line I'd chosen, regardless of where he thought he was going. It was a good lesson to me of ikkyo's effectiveness.