D&D 5E (2024) Converting My Sorcerer/Warlock to 2024 + Adding Psion?

[Dragonhelm]

I am currently playing a halfling aberrant mind sorcerer 5 / GOO warlock 2 in my friend's Spelljammer game. In our last session, my character met an NPC psion (UA playtest version), who taught him some medication techniques to help him unlock his mind's potential. The DM said that the next time we leveled up, I could take a level of psion. We leveled up at the end of the session.

The game uses the 2014 rules. I asked my DM if I could update my character to the 2024 rules since the GOO warlock's psionics are more in tune with other psionic classes. He's looking into it, but I don't have a response yet.

In order to make this work, I would have to change his levels to sorcerer 4 / warlock 3 / psion 1 so that he could access the GOO patron for warlock.

Is there anything I'm not thinking about that I should look out for?

And as a quick aside, I got the inspiration for my character's name from this very forum. I named him Merric Willowshade.

 

[Kobold Stew]

It's not clear what you think a level of Psion gives you that you want. I suspect you aren't doing yourself favours by going into a third class.

Sorcerer 5 will give you third-level spells, and at level 6 you can cast the psionically, if that's the flavour you want.
Warlock 4 gives you a feat, Warlock 5 gives you two new invocations, and at 6 you can cripple an enemy with your brain.

Depending on your playstyle, you could justify 6/2, 5/3, 4/4, 3/5, or 2/6, and all would be as fun as adding a level of psion, with more high-level spells in play (I would probably pick Sorc 3/Warlock 5). Plus, the psionic feats are also good.