My clan used to lose all the time but...
We're on our 8th winning streak.
We kicked all the inactives and lame attackers.
IMHO clan wars is a team game - it is not meant to be won individually but as a team therefore if i see anyone attacking with tier 1 troops it is a red flag for kicking.
Also it's okay to be premmie in terms of defense but in terms of offense as a team you should always have the most up-to-date troops.
Edited :
And also, because clan war matchmaking is measured by combat strength - walls, towers, troop levels, and heroes' levels, in a clan where the combat strength varies greatly, one may not expect lower ranked members to carry stars. It is the top ranked member's responsibility to win the war.
If this is the case of your clan, you should focus on your core attackers to win the war and let the lower ranked members farm (getting at least 1 star and resources to upgrade).