Some points that may help with the wizard running out of spell discussion while trying to be somewhat neutral.
Ignoring 4th level wizards is probably fine as those groups tend to be slower, running out of spells less likely, and playing at normal/hard. Where they do run out of spells, consumables (spells/wands) have reasonable damage at that difficulty and landing a hit with a staff or sling is challenging but generally possible. Edge conditions of experienced groups playing at 4th level as a challenge don't seem necessary to design around.
5th level wizards have 14 damage spells, 1 in combat buff, and 1 in combat utility for 16 rounds of stuff to do.
5th Elf wizards have 12 damage, 3 in combat buff, 1 out of combat utility for 15 rounds of stuff to do.
I think the following list would be the tokens that currently attempt to address running out of spells:
Extra damage spell as a spell (with bonus): crown of expertise; charm of spell swapping; ring of spell storing
Extra damage spell without bonus: +2 staff of power; tome of insight; earcuff of energy
Damage Consumables: scrolls (potentially with sage speed); wands (potentially with mystic mouth)
The recast with bonus options I believe are all viable in builds at all difficulty levels. I've used them on druid. It can be a difficult choice to put spell storing in a ring slot, but is comparable overall dungeon damage to +3 focus so is not a ridiculous decision to have to make. I think if one is concerned about running out of spells the head slot is going expertise. Charm slot is quite contested, but for casters other than MEC I'm not sure what would be higher priority for a damage focused wizard. If a new token in a single slot is created allowing infinite ranged attacks with bonus, these 3 tokens become less interesting but not completely superseded (these don't require sliding depending on selected spell).
Recast without bonus tokens don't really help at the nightmare/epic level so shouldn't be considered.
A single rare scroll averages around 10 damage. A single rare wand blast is around 7-8 damage (potentially +2 if a wizard wants to equip for that). That's probably 20-33% of the damage that either a melee or cast-with-bonus spell round would do at the nightmare/epic level (though without the chance to crit so consider it a bit lower than that). A second consumable could be used if one builds for that allowing 40-66%. It is worth considering both if consumables can be considered a viable solution to running out of spell slots (real world cost) and if so is the overall damage output from a nightmare/epic wizard close enough to top end that a few rounds of 50ish percent power would be reasonably balanced (find the big detailed output analysis spreadsheet from last year). A potentially interesting item would be a wand that requires sliding, fixed 15 to hit but can crit on a 20 or crits if a mark on the token is pointing at the damage marker on the board maybe.
Ignoring consumables then Wizards currently have 15-17 rounds of damaging attacks and 1-2 rounds of other stuff.
From a balance side of things, at least 1 of those damage rounds and possibly 3-4 impact all enemies if the dungeon has them. I don't think any other class can really do that (bard to a lesser extent, ranged physical attackers to a lesser extent and with the correct consumables).
Grind you're looking at potentially up to 18 or so enemies in 6 or so combats (but there seems to often be a way to cut that down somewhat with good decision making/role playing). There will almost always be multiple enemies available, so 15-17 rounds of attacks is 16-21 enemies damaged. Given the exposition and decision time, you're probably looking at 25 or so rounds for an experienced group in grind? At nightmare/epic level with highly efficient group the difference between the card and total rounds is potentially around 10 rounds. That is a lot to cover with consumables, but in grind at that level I would think most classes are burning consumables as well. Potentially rather than tokens possibly consider a mechanics change in grind like an option for the group to take a rest to recover some number of spell slots and hp at some point in the story.