Exactly. I'd rather play in the CL because the measure of any team is how it performs in the league. If we're good in the league, we'd qualify for the CL. There's no other way. You can't fluke your way into the CL, but you can definitely fluke your way into winning a cup like the FA Cup or the League Cup. Playing in the CL also enhances your chances of winning other, more meaningful trophies and enables you to compete in the long-run for every trophy. Winning an FA Cup will be magical for that one day, and maybe the magic will last until we're inevitably knocked out by a better team in the next season, but consistently playing in the CL will mean so much more for the club's long-term chances.
The goal, for any club, has to be consistently challenging for trophies and performing well in the league. That's why I'd easily and without doubt forgo winning the FA Cup if it meant that we'd get to play in the CL.