I shudder to think how badly the current squad would fair in a CL campaign. We are a hundred miles away from being ready to compete at that level. The trouble we've had in recent seasons' Europa League campaigns as soon as semi-decent opposition crosses our path more than demonstrates this point. If we can't dispose of the likes of Fiorentina, Lyon, Basel etc, we will be torn to shreds by the teams we'd face in the CL.
One of the reasons our maiden CL voyage was so successful was that we had a once-in-a-generation blend of players who had bags of CL experience (Gallas,VDV) together with players who were clearly and demonstrably good enough to compete at that level (King, Bale, Modric). The level of our squad now is nowhere near that level.
I get that 'The game is about the glory' and all that, but there's no need to 'rush' things when one disastrous season in the CL could knock our youngsters' confidence for six while ruining our respectable coefficient at the same time.