How about to increase the QM ladderboard creating a clan rating?
That's all that's required imho. Just add a "play as a Clan War game" checkbox on the QM dialog box.
If we absolutely need timeslots to ensure there is enough clan representation, make it hourly, even 30 mins. It should be a more accessible thing, smaller events throughout the day (more like WZIB), not big events which need mass participation to succeed.
Get rid of free wins. Scrap the fixed templates. Let everyone play what they want - just like QM, let people select the templates they want to play. Add another row, so it's QM RT, QM MD, QM CW RT.