I think I’ve got this right as the list of spells that I’ve either removed concentration, made it able to be removed by casting the spell using a spell slot 1 higher or able to be removed using a spell slot 2 higher (when electing to remove concentration by up casting the caster doesn’t get the other benefits of upcasting ie when casting fly using a 5th level slot you can either affect 3 people with concentration or one without - but using a 6th level slot you can get 2 without)
Concentration removed: Incendiary Cloud, Flesh to stone, Mordenkainens Sword, storm of vengeance, weird
+1 level: Alter Self, Barkskin, Blade Barrier, all detects, enhance ability, enlarge, entangle, evards, fear, gaseous form, Giant insect, Globe of invulnerability, Hold monster/person, Hunger of Hadar, Hypnotic Pattern*, Insect Plague, Invisibility, Levitate, Major Image, otilukes Resilient sphere, ottos dance, phantasmal killer, polymorph*, protection from energy, Ray of enfeeblement, reverse gravity, Silent image, sleet storm, slow, spider climb, spike growth, stinking cloud, stoneskin, sunbeam, Tasha’s, telekinesis, vampiric touch, all wall spells, web, witch bolt
+2 levels: Beacon of hope and all the Aura spells, Blur, Calm emotions, circle of power, crusaders mantle, Expeditious retreat, Eyebite, Faerie Fire, Flame blade, flaming sphere, fly, fog cloud, Greater invisibility, Gust of wind, Haste, Heroism, Magic weapon, moonbeam,
I’ve asterisked hypnotic pattern because I’m alert to the possibility it might be too good at +1 and polymorph because I am alert to the T-Rex use of this spell and I have also made the beast limit cr of 1/3 caster level but I’m thinking of making it the spell slot expended ie to turn into a cr 7 giant ape costs a 7th level slot as most 5e spells scale by slot used not caster level.