For Bastion, you can switch to Turret and Tank form in the skin selection menu, so you can see what it looks like. It would be nice if this would also be possible for Wrecking Ball in his ball form. I know the main focus for the devs is currently OW2, but this doesn’t sound like too much work, and would be a nice addition to OW1 (and perhaps OW2 as well, if it isn’t implemented there yet either).
Another less prio suggestion: a way to view every skin with a toggle, even those you can’t really get anymore. Like the 2019 Atlantic All-Stars or Pink BCRF Charity Event 2018 Mercy skins for example. You may not be able to get them anymore, but we can still admire the work the design department put into them in the skin selection menu that way. Right now you can only see them if you play with/against someone with them in game, or by searching for them online.