well of course no amount of tit-flashing is going to be classy. Keijo as a sport is not classy.
Keijo as an anime with hidden nipples is classier than others in its class because it plays down the ecchi aspect and doesn't try to make things entirely perverted like innumerable other shows (that flash tits).
Repeat: it's not about making Keijo-the-sport a respectable competitive sport like Judo. It's about keeping the nips hidden on screen so I don't feel like a degenerate hentai.
That's the fine line between funny and weird.