Rune mage, a sorcerer subclass

[Gnomes2169]

1. This doesn't sound like you have a theme but just that you wanted it. What does runes have anything to do with a panic button or surging? Again Reckless Power seems to be the odd one out without some specific lore. I don't have any problems with the power as I know it is once a week or 3 days, but if an ability like that is really used so sparingly it begs the question should you have it in the first place.

Hmmmm... Maybe modifying it so that it's a very high cost sorc point ability instead of a week long cool down would be in order. The rune mage is fluffed to use runes as foci for magic and power as is, so it would fit there and fix the whole "has no subclass abilities to spend sorc points on" problem. Maybe 4 points, so that you could use it and still regain a level 1 spell slot at level 6...

2. No, the idea of this is that is they have an alternative spell-like ability. This only further expands the amount of spells they have or modified. This also brings up an issue is that currently it is the best metamagic user as well as the most spells.

And I'm going to try out making Reckless Power into the rune mage's sorc point ability. As for the best metamagic user... The rune mage applies their free metamagic only to one of (up to 9) spells. At level 14 (when you get the ability), this is a total of 7 spells, that may be modified with one of the following metamagics for free:
Careful
Distant
Empowered
Extended
Subtle

None of these will break a spell beyond belief, and being able to apply any two of them to a spell for the price of one, while useful, is no more powerful than infinite flight (Draconic sorc) or rollong wild surges twice and choosing your result. (That said, wild mage can definitely use a power boost)

3. This is what it says, "When he gains access to a new sorcerer spell level, he may select one spell from the wizard or cleric spell list (spells chosen are cast off of charisma) to write as a rune either on his body or an object in his possession....Effectively, this gives him one extra spell known and prepared of each spell level." What is the point of both known and prepared in the last phrase if they don't get another slot each level?

This is 5e, not 3.P or 2e. Spells known/ prepared are entirely separate from your spell slots (you prepare by class, not slot), and that line literally means what it says. Every time you would gain a new spell level, you learn a new spell (gain a spell known) and it is treated as prepared. So one more spell known and prepared of each spell level. It doesn't do anything with your slots beyond giving you more things to speld them on.