The screen touch sensitivity got on my nerves too.

It shouldn't be an issue with just a silicone case since it should just slide right off. It will not fit in the Wahoo with any case on it.

To me the lifeproof case isn't bulky at all compared to the Defender. It's must faster and less trouble to just pop it in the lifeproof bicycle mount. But again that's just my preference. You may be fine with loading it in the Wahoo each ride.

I also consider getting off the bike and taking my phone with me, etc. There's other advantages as well like being able to use the Blue HR while not in the Wahoo case, but may not apply to you.