Before finalizing the first pages/panels, just try out some different options and see what works.
Look at the difference:
The first(Wild Words) is clearly superior to the rest, but the second one (Blambot Pro Lite) could also work. The bottom two (Arial and Angeline Vintage) both look unprofessional. While Arial is easy to read, it also looks boring, like no thought was put into the text at all. The last one is just difficult to read. The capital i especially looks bad. Capital i is a very annoying letter when it comes to script fonts.
I think it's really important to stay within the realm of a legible, workhorse, comic font for the main dialogue and agree with Kura that if your text is hard to read, then you have failed at the communication aspect of comic making. Unless your goal is to make the text difficult to read.
I purposefully did not add a white border around this text so it isn't completely clear to read:
To repeat what JeanGullet said, you really have to know the rules before you can break them. You can break them, but it has to be in purposeful way that adds to the comic and doesn't detract from it.
As for handwriting the lettering, bad/good handwriting... it matters somewhat but the thing is that lettering is different than your handwriting. While they may look similar, you can't just write normally. You have to really draw each letter individually and make sure every letter is neat and has good negative space.
I do think it's good to get in the habit of hand lettering some text at least. Please... don't use fonts for SFX. Not to say that they can't look good, but handwritten SFX almost always look better.