13a keeps the attack spells.
13a barely has high level control spells [...]
The top level wizard spells are Teleport , Meteor Swarm, Disintegrate
This is not really true. Spells scale with level, so for example, a wizard at 10th level casting
confusion (first available at 3rd level) targets a standard 10th level enemy, confusing (and with a feat, dazing) a large spread of opponents at 10th, and even more at lower level, uninjured. This scaling further essentially means that the wizard's top level spells are the whole set of spells. Additionally, many wizard spells are a combo of damage plus debuff, compared to a sorcerer tending towards raw damage; a wizard may look like it only has damage spells, but that's only if you compare their spells by name --- to my point of needing to see the whole game to evaluate power level.
(To be clear: I am citing the recent 2E here, but scaling and spell availability was basically the same in 1E, just without a 9th to 10th bump.)
13a barely has high level [...] caster enemies.
And there is no Archmage enemy. The Archmage and Lich are Uber NPCs
The icons are not statted, but that's not important. The game has 10th+ level sorcerers, wizards, casting dragons, demons and devils, etc., filling a caster or spoiler (your typical control type) role.
What the game doesn't have is enemies built like PCs where you give them PC class levels, largely because it's a lot of work, but also because it's completely unnecessary --- they made the math work to the point that a 14th level uberwizard has a baseline stat array and then you pick or construct the spellcasting effects it has. This may sound like DIY effort, but it's simple enough to do it on the fly.
The point I want to make is not that 13A is exceptional (though I think it's exceptionally great), but that they thought through the game at high levels. How did I know a 10th level
confusion targets a standard 10th level enemy uninjured? Because the math is right there: it targets creatures of hp 400 or fewer, and a standard 10th level opponent at baseline has 240 hp (a significant 10th level threat is more like 720 hp, or a standard 12th level threat baseline 400 hp, for context), clear as the tables they're written in. This scaling is abstractly true regardless of type: fighters' damage scales with their basic attacks and martial effects, bards buff and debuff with increased effectiveness, etc., and the high level threats follow a mathematical framework where the GM knows what to expect of the tools and has an ample roster to draw from, because high level threats don't need complexity patches or mob rules or etc. --- 13th Age crunched the 20 levels into 10 the right way, because they focused on all 10 of the levels, and (opinionated statement here) weren't constrained by bounded accuracy's drawbacks. I think 13th Age is a great example of how the number of levels doesn't matter, but the cohesiveness of the whole spread of those levels does.