At first the EM dashes didn't seem that annoying, but by the end, I also agree with the two above.
First of, the EM dash is for stressing things, so try to avoid it unless that's the case, which probably shouldn't be more than 1-3 times per chapter, depending on length
For attributes, bind them to the word they actually belong to
His body—naked—looked[...] → His naked body looked[...]
For larger structures, make them independent sentences or subordinate clauses
[...]in his academy—the administrative[...] → [...]in his academy. The administrative[...]
[...]hanging above the table—a date marked with[...] → [...]hanging above the table, presenting a date marked with[...]
Those are just suggestions, but I hope you can get my meaning.
The tables are a matter of preference, so I can't tell you whether to use them or not, but there are a few things I think you should keep in mind.
They break the reading flow. Think: Everything halts as Arc stares at the info screen.
For the current three tables that kind of makes sense, but I'd suggest you refrain from using them in excess later on.
If you need them, focus on important info. Leave out the rest, or highlight the bits you're going to talk about next.
Adding a pre-formatted table for every new item will just lead to readers skipping them, worsening their reading experience due to the breaks and giving you unneeded work.
The ones in chapter 1
Class: merge the free/paid columns, since you point out the price either way
For the awakening locations and skills, you put a huge list of names, but none of them seem particularly important.
Since you say that there are more either way, why not keep it to a short few?
Name generators are convenient, but they should be used in spots where it's better to have a name, not in any case it's possible.