Hiza guruma to hiza guruma/sasae tsurikomi ashi
One of the slickest follow-ups to a hiza guruma that didn't quite work is a second hiza to the other side. The trick here is to take the foot that you initially put up for propping uke's knee on the first try (let's say your right foot), and put it down pre-turned, inward. If you don't, the angle of the second hiza will be all wrong and plus, you'll miss out on the power that a coiled hip springing into action gives you.
We also found that for smaller players, stepping close to uke at a right angle on the second throw and catching a sasae tsurikomi ashi worked well.
Incidentally, this same action of pre-turning the foot also sets up the nice kosoto gari I mentioned in the last renraku waza post.