If you increase your comment upvote to a dollar, I imagine at first you will get around the same comments you do now. If, however, you continue the experiment longer than a week and give it time for word to get around, you will attract more people just after money than after really connecting with you.

I generally upvote comments at 15%, which at my stake is about 5 cents. Sometimes if it's a really good comment I upvote around 30%. I feel the same as you about wanting to reward people for taking the time to comment. It's a "thanks for taking the time", more or less. You might laugh, but my biggest motivator for increasing my stake is being able to give out decent rewards without having to raise my voting percentage too high.

I suppose 5 cents isn't much of a motivator, so I don't have a huge problem with people coming in and trying to farm my goodwill, but I do get them sometimes. Funny thing is, my regular commenters have commented on my posts even when my 15% upvote only have a single penny. The only people I have attracted by my increased upvote value is people only after money.