Your highest town hall players in your clan should be filling your war bases with high level troops, and you are certainly welcome to request troops of higher level than you can donate yourself.
As for your war base, keep in mind that as you go higher town hall levels you're gonna get attacked by very tough armies. Always always centralize your clan castle, and protect your splash defense as much as possible by multiple layers of walls.Storages mean nothing in Clan Wars, use them to tank hits on the outer layers. Because you don't lose any actual loot when attacked in Clan Wars, protecting storages should not be done in a war base.