I said earlier in the season, we look at the CL as having an extra couple of games already and potentially 4 more if you have to do the playoff for the last 16.
But we could have looked to play a reserve team, as we do in the league cup and still made the playoff. That way, whilst you play more games, in theory you're resting your first 11 more than you did in the previous group stage competition.
I wouldn't have prioritised the league cup either though. I'd have had a first 11 in the league, and then one for the CL. We'd still pick up enough points to make the playoff, possibly even to go straight through.