D&D 5E Help with Roguish Sorcerer (Wild Mage) build

Would like a bit of advice on a character I recently built at lvl 2 to join a new group. She's a Sorcerer with the Wild Mage, but I've also been playing up her roguish behaviours - her basic concept is that she's a street urchin - talented thief/pickpocket - half-drow (though doesn't know this herself, and to most appears as a rather sickly looking half-elf) who's recently started developing magical abilities which manifest when she gets angry/under stress.

I was orginally going to stick with Wild Mage, but have found the DM isn't all that keen on rolling on the Magic Surge table all that often which I think makes the class a little underpowered, so I'm now thinking about how I might change her up.

Currently she's at lvl 2 as a wild mage sorcerer, and her stats:

S: 7
D: 15
C:14
I: 10
W: 12
C: 18

Prof. in Deception, Insight, Sleight of Hand, Stealth

Would it be feasible to multiclass her into rogue (arcane trickster?), keeping the character concept intact? I can see the intelligence/charisma thing being an issue, but if I could get the DM to accept charisma as the spellcasting stat for the trickster?

Otherwise, it may well be a better idea to just ask to reroll and go full rogue.

Any opinions would be much appreciated.

Thanks!!

Subtle meta-magic is great for such things. subtle+charm someone in the middle of a crowd. Or subtle+invisibility when you put on a copper ring, then sell it as a ring of invisibility. etc...

Rogue is a steep trade-off for a sorcerer's higher level spells. Not saying to not do it, but just keep in mind what your losing as well as what your gaining.

No wild surges effectively means you are not a wild magic. See if he will allow the shadow sorcerer. https://media.wizards.com/2015/downloads/dnd/02_UA_Underdark_Characters.pdf

Warlocks can pull off a very good "magical trickster", and they lose less when they multiclass. so they can work well with rogues or sorcerer's.

Also finally, just because a class/combo is underpowered, doesn't mean it's not fun.

If the DM is not keen on rolling on the Magic Surge table, then you should talk to him about changing your sorcerer to a draconic sorcerer. You have a lot of choices for your idea. Different combinations:
1. Rogue 14th/ sorcerer 6th level. This build uses spells to enhance their rogue capabilities.
2. Sorcerer 17th/ rogue 3rd (you loose one ABI but most campaigns don't make 20th level so it does not matter). This build uses spells to replicate rogue abilities but it can act as a full sorcerer as well.
3. Switch to a Bard character. Bards make alright thieves with spells.

Don't worry about your character being underpowered. The idea is to have a character that's fun to play and contributes to your party. I played a 3.5 campaign wit a magic user who had a 3 strength. It caused some interesting issues until he found a magic carpet to fly around on in the dungeons. Eventually, he got tired of being barely strong enough to hold his wands so he made himself some gauntlets of Ogre strength.