1. *edit: fixed
2. There's something new and annoying for me: you've added something that hides partially the bigger signatures. If I hover my cursor over a signature, it expands the whole thing and if I move away, it reverse it back. I really, really want to turn this feature off! It really gets me annoyed while reading the posts. Or even better: add an option to be able to turn signatures completely off. I really don't care about people's images in their signatures. They're just taking more space and don't want them to interrupt with my experience while browsing this forum.
3. *edit fixed.

You can disable signatures on your user settings page.

Ah, thanks! I thought that option would show/hide only my signature. You may edit this to make it more clear for others that this option will show/hide all signatures.

Though I preferred the old way signatures were handled (not expanding, just show everything. Is there a way to make it do this way?

No, I consciously made that impossible because signatures shouldn't have been this big to begin with. I think there was a rule setting a max size at some point, but it hasn't been enforeced in ages.

Ideally signatures aren't larger than the message itself. Even with the current rules that's not necessarily the case, but at least it's better than before.

(I guess if you really want to see the full signatures you can use NoScript or something to block https://www.jazz2online.com/scripts/forum.js. Though that's not guaranteed to keep working forever)