I enjoy high magic. I want high tiers towork even better - and more smoothly.
For players who prefer low magic, optional mechanics to end advancement at a low tier, in a way that is satisfying, seems like a worthwhile effort.
When dividing advancement into 4-level tiers that correspond to proficiency bonus improvements, each tier feels different. It is worthwhile to understand each tier.
The lowest tier 1-4 feels fragile, very much like student apprentices, like students alongside Harry Potter.
The next tier 5-8 is probably the "sweet spot" that characterizes the essence of the D&D experience. Powerful magic wizards and powerful natural fighters coexist side-by-side.
The third tier up 9-12 is still "sweet" but the feel changes. This is the level when player characters become movers and shakers who shape the world around them. Traditionally, this is when player characters attract followers, found institutions, run governments, lead armies. They game becomes a bit more like collective world building. Characters still go on personal adventures, but the scope feels different. This is a game like Risk, of nation rivaling nation. With regard to the lower tier "sweet spot", this higher tier can feel like a satisfying accomplishment, a reward for a game well-played.
The next tier up 13-16, becomes a game of superheroes. As enviable as the vast damage is, that the natural fighter can deal, the magical wizard seems able to evade it, thus outmode it. The fighter becomes dependent on magic to keep up, whether by magic items or by ki-like mystical feats. Everything is superpowers. But D&D remains to develop this super genre further.
17-20 is Wish and planet altering superpowers.
21-24 is immortality and shaping universes. A game of world versus world.
It seems useful to think about these tiers more carefully. To jump into the game, depending on the king of game they want to play.