Yaarel
He Mage
Right but that slowdown for slots 6 to 9 is true for all fullcasters, including both Wizard and Warlock.Wizard slot progression drops to basically one maybe two of each level around 5th or 6rg level slots. I'm on my phone and can't check it now, but it's a big problem for full casters because it makes the opportunity cost for a sorc to take 2levels of warlock for repelling agonizing blast basically just one spell slot at the gain of an at will 4th or so spell level equivalent.
Your warlock complaint can get in line behind fill casters with borked slot progression
The design seems to have each new level be about the same unit of power. Thus at a low level, to gain a slot 2 is worth say 3 points. So the level still has points left in the budget to purchase more than one slot plus additional class features. However, at a higher level, to gain a slot 7 is worth say 9 (?) points, so the budget for that level is already spent with not much for anything else. Whence the slowdown.
This linear progression can include some features that are shockingly arbitrary, like putting a less valuable feature at a high level and a powerful feature at a low level. But overall, the roughly linear progression allows the nonmagical classes to keep pace with the power of the magical classes.