CapnZapp
Legend
I value your feedback, and certainly the "too specific" is a valid criticism.Those items seems ludicrously specific as to who might be able to use them. The chance that someone would find the ring and know one of the relevant spells and be in a situation where that warranted spending multiple spell slots is vanishingly small.
If you're comfortable adding stuff to the game, why not just invent new spells that work exactly like the bad ones but don't require concentration? Inventing new stuff is encouraged in this edition.
Just dropping concentration is, however, not a productive path forward, in my opinion. The whole point is increase versatility but not overall power. If you merely drop concentration, not only have you made the spell plain better, you have also made it possible to combine it with the best-in-class concentration spells.
The idea here is to identify a set of "second rate" concentration spells, and make them compete better by being workable in pairs.
Instead of concentrating on one good spell before you start to Fireball away (or something), you would be given the option to concentrate on TWO less good spells.
That's the idea anyway.