I agree we need more killer instinct in the final third. I don't think it's posession for posessions sake at all though really.
In my mind we're doing better this year because we (mostly) don't look afraid of having the ball. Not saying we're playing like peps Barca but in comparison to last season its night and day the amount of control we have in games. Playing the way that you suggest would put our back 4 under massive pressure to keep a clean sheet, as if we conceded first the opposition could just sit back and defend and we wouldn't have the system or the right players on the pitch to break down a low block.
Could argue it might be a worthwhile tradeoff if Beto was absolutely clinical, and was likely to score every time we play him into space, but he isn't. Our best players are KDH, Grealish and Ndiaye - we should be playing to their strengths, and trying to maximise their influence. Beto and Alcaraz are not the players we should be building our strategy around.