Even if you go E6 with it?
In my current game we are pretty much at the point. The PCs just hit 7th level at the end of our last session.
Working with some other DMs we have E6 (and higher) variants, but this group has two new(ish) players, one
brand new just joined us last week, and only one experienced player who helps me with homebrew/ house-rule stuff.
So, as such, I am trying to keep it as close to RAW as possible for the new players to let them learn "by the books".
But anyway, as just for the "going E6 route", that helps but for myself I'd be all for slowing things down and "expanding" the first 6-7 levels over 11-12 levels, giving HD at each level, but without the CON bonus, and still using creatures as if playing with normal level advancement.
For example, one PC is a half-orc Fighter with STR and CON 20 (rolled two 18's and decent scores to go with them...). He just topped over 100 hp thanks to some rolling and the
Tough feat. He has AC 19 thanks to the
adamantine plate he forged after finish a quest helping some dwarves, has
Dual Wielder for the AC bump and two longswords, one silver, one also adamantine. Thanks to Two-Weapon Fighting style, he consistantly deals about 25-30 damage per round, and none of this includes his Rune Knight subclass features, which are substantial IMO but he really liked the concept so I went with it. But I've even had to go to the point of nerfing his Rune Knight features a bit! Granted, rolling scores he got lucky, especially as it's his first 5E character! But, I saw the rolls, so I know there was nothing shady going on there. All told he is a tank and consistent damage dealer. That is his role and he's really happy playing it, so that's good.
The other PCs in the group, all powerful in their own ways, are pretty much on par with this one. The 5th PC is joining this week, an evoker Wizard. So, now in addition to the tanky fighter, nova paladin, ranged sneak-attacker rogue, and healer/support sorcerer/cleric, we have AoE-artillary. The power level just seems crazy at 7th level.