I think you got the rating you deserved, tbh. Five out of ten is fucking GOOD. People freak out too much, but Ten Stars is fucking, Broadway. Five stars is what an independent production should aspire to. If people were less anxious about the rating system, things would sort themselves out better - you should be proud to have five stars, and be chilling with other five-star artists and working your asses off to earn six stars.
I can see what you've done here, asking for help manipulating the system, as a good thing meant to get you better exposure, but I think you should instead work on seeing those half-ratings as a good thing before you try to get something better. There's only a few things worse in creative work than getting a compliment you aren't equipped to handle - it's like a weight that falls through your floor into your basement. It might crush something or someone that lives down there.
I've seen your comic - it's amazing. It has a few problems that I think are worth taking five out of ten stars worth of time to look at:
1. The episodes are way too short. You're putting in a grand effort and getting little results. You could conserve your energy until you have five pages at a time to post, and post them weekly, and it would be a much less frustrating browsing experience.
2. Your watermark/link image at the bottom is way too big and distracting. It's good to attract a little bit of attention to the financial/social side, but not THAT much.
3. Your art is beautiful to look at, it just doesn't have the tension and razor-sharp brevity that a master work has. These are works created by decades-learned artists under intense pressure and deadlines, for a guaranteed audience of at least a million. Your work is soft and chill and floaty, but without the counter-balance. It needs to hate itself just a little bit, so the audience can love it back up to size, if that makes sense. It's a sacrifice that you or I wouldn't be ready to make because we're still attached to the idea of loving our own projects. That's why we sit at five stars, not ten.
Hopefully that's a helpful, not-too-critical explanation of why you're actually perfectly fine right where you are, and it's the stigma of 50% that's holding you back, not one guy giving you a bad rating.