Love: if the premise interests me at all, I go for comics which have good colouring, lines and composition. I like to know that the creator has actually studied for this, who have put in the time and effort to research the nitty gritties of making comics. Even if it's not quite there, if I can see that there's potential and the creator is learning and improving, I'll stick with it. I also gravitate towards comics with visually interesting but not unrealistic characters, they have to feel 'real' to me. Also lettering. Poor lettering will turn me off a comic IMMEDIATELY, but good lettering might keep me reading long enough to get invested.
Hate: Not so much hate but, things I won't bother looking at a comic for. I'm really biased against comics written by Westerners (read: Americans) which have japanese/romaji names and a juvenile 'anime' look about them. On its own, the anime style isn't a bad thing. It's the title that really makes me immediately close out. It just comes across as "fourteen year old weeb" and no offence to kids who are in that phase, but I grew out of it years ago and it's not for me. I also don't read comics where it's clear that the creator has no idea where they're going with the story. If they're just fucking about, I'm not really interested - I read comics for characters and story, so if neither are fleshed out and concrete, I'm not going to bother staying with it.
The only other gripe I have about it is not with the comic itself, but more the creator (on tapastic). It really irks me when I keep getting notifications that the creator is streaming, and when they do an episode update which is basically "sorry no updates this week" or "here's a fun special thing". That really interrupts the narrative flow for me and I don't care enough. I've unsubscribed from a few comics because of the streaming notifs, too.