I find the taboo of downvoting a bit stupid. Now I'm not saying I'm going to downvote every post someone makes that I disagree upon, but if I'm actively participating in a discussion and I see others upvoting posts with 'Agreement' as the sole reason, I'm going to join them, but on my way:
Upvoting comments/posts I agree upon and downvoting comments/posts I disagree upon. It's that easy, really!

If I had a higher upvote value, I would just make it a certain percentage. And believe me, even for a 48-rep, my downvotes don't mean a lot. Of course, it'll have some sort of an impact if I downvote every single post/comment they make, but I don't do that.

If someone decides to destroy my rep, I move my steemmonsters cards to an alternative account and everything I got on here. Problem fixed. If they wish to waste money on destroying my rep, I would naturally be disappointed in their behaviour, but it would not be the end of the world. If someone downvotes me with 100 SP, I'd likely not even notice.