For sorcerers in my game I use the spell point variant from the DMG.
I add the sorcery points to the spell points, and make it one pool, called sorcery points. PHB sorcerers can pretty much exchange sorcery points for spell slots (and vice versa) anyway, so it reduces bookkeeping to just combine them.
To make them stand out I allow sorcerers to overchannel. For spells with an "at higher level" effect, sorcerers can cast them at a level above what they would have spell slots for, as long as they pay the cost in spell points. They can only gain one additional spell slot of 6th-9th level thru overchannel. This lets them "go nova" a couple times a day.
I wholeheartedly agree that the Sorcerer should have automatically been given the spell point variant option, which would have made them different from other classes, as the warlock with its spell slots. This would have also affected multi-classing as in the warlock class.
In addition, spell points would have eliminated the loss of sorcery points when you "sold" spell slots for sorcery points at a loss, then having to "buy" spell slots at a premium.
We made the same modification as you by using the spell point variant and added sorcery points
The other changes we made were
1. We allow the sorcerer to create/cast 2 6th level spells at level 19 and 2 7th level spells at level 20
2. Added more metamagic known and created more (homebrew) metamagic
3. Allowed recovery of 1 sorcery point after each short rest starting at 2nd level and increase by 1 every 4 levels.
4. Added more spells to the sorcerer list from the wizard spell list
5. Increased the flat number known to 22. It made no sense that a 1/3 level caster who uses spells to complement its core abilities would know as many as a primary caster who's spells are their core ability.
6. Archetype spells were offered as an expanded list as the warlock archetypes