I hadn't considered the additional branding factor as it's indeed more weight on your shoulders in terms of marketing but assuming it helped reel in customers I'd imagine that the costs would be hopefully justified although it's true what you said about it being more of a risk for a smaller company. As for them being silly, it probably would be a bad idea to have some ridiculous character to misrepresent your business but say you had a name like FrogHost, a frog mascot would not be silly in that scenario assuming it didn't look like a Disney cartoon so it would feel more essential in that case in my opinion.