That's why I'm thinking more of a disease than just him having BOTH eyes eaten. If you didn't notice them missing, are you sure you'd have noticed them bulging?
He probably wouldn't have caused any problems at all with your plants. Mine at least is very calm most of the time and even when I'm lucky enough to see him out he's calmly gliding around.
Seriously though, they'll eat practically anything. Mine does anyway. Just races around the tank hoovering up whatever food he runs near. Angel fry might get eaten, but after a month or two they'd be far too big for the Pictus to eat. Neons and things wouldn't be hard for them full grown though. Imagine trying to swallow a small plate compared to a sausage.
Nope, pictus cats have no personality at all. Horrible horrible fish, pet shops won't take them back so don't even bother trying. Only thing you can do is sell them to me. I'll give you $5 each.
Nope, won't cause any problems, IMO you're better having it wide open and pointing it against the glass or similar to reduce the current, otherwise you're just wasting.
I had a look at it a week or two, very nice looking guy.
I also asked them about them losing a few fish in their big tank. They said basically, NO we didn't lose any, a bunch of them went up to Auckland though.
Sharp substrate is generally pretty bad. But, could be doable as long as you don't have any bottom feeders. Finer substrate almost always looks better though.