I was thinking about playing a Wild Magic Sorcerer, but roll on the wild magic table every time she casts a spell. Any thoughts?

The playtest had a thing where you can choose to roll in the table, I think it was 1/long rest. Or maybe it wasn’t written down , but that’s what JC said in the video. There was definitely something to boost it. You might look back over that info. 
If you’re going to play one, I would recommend something like that. I was in 2 games recently with a wild magic sorcerer. Across more than 50, maybe close to 60 sessions, only 1 time was there a surge. And I don’t mean 1 time each — one player never got one at all. 

Rolling on the table every time you cast a spell would be a bit much. There are two main ways of rolling on the table, and they're enough, with some caveats. The following is what a player in one of my campaigns did and it produced a fairly even spread of wild magic surges overall:

We assumed that I as the DM always make him roll the d20 specified in the Wild Magic Surge feature:

Starting when you choose this origin at 1st level, your spellcasting can unleash surges of untamed magic. Once per turn, the DM can have you roll a d20 immediately after you cast a sorcererspell of 1st level or higher. If you roll a 1, roll on the Wild Magic Surge table to create a magical effect.

Second, the player used his Tides of Chaos feature frequently. If you assume that the next spell after you used this feature always triggers a wild magic surge, you have frequent surges and also frequent sources of advantage - which is a double blessing if you like the surges.

Any time before you regain the use of this feature, the DM can have you roll on the Wild Magic Surge table immediately after you cast a sorcerer spell of 1st level or higher. You then regain the use of this feature.

These two ways of triggering a surge are built into the class and they alone are enough to give you plenty of surge triggers without being completely overwhelming. All they need is for the DM to be on board.

A houserule I created that got used in a game was every time you cast a spell of 1st level or higher, roll a 1d10. If the roll is equal to less than the spell's level then a Wild Surge occurs. 

This made the surge more frequent than the basic 5% chance of RAW, which used to almost never occur and the chance of a surge increases the higher the spell's level. It worked out very well.

If you/your DM still feel like this is not enough, I feel like the VLDL campaign has a good amount of surges happening in it.  The changes from the above are that if you do not trigger a surge, the next roll triggers on a 2 or lower.  If you still don't surge, it goes up again (to a 3 or lower), continuing on until the surge happens, at which point it resets (long rest resets this mechanic).  Tides of Chaos also isn't a choice for a player to either long rest or trigger a surge to get it back.  The player AUTOMATICALLY surges on their next spell once they use ToC (which resets ToC, of course).  Note that both this and the vanilla versions trigger more often at higher levels (as you are casting more spells before a long rest), but this variant REALLY ramps it up the more often you cast.  

...Baradun is like 8 feet tall now...

Still not enough?  Tie it to using MM as well somehow.  Maybe every sorcery point you spend modifying a spell increases that threshold as well.

The thing with rolling EVERY time is that there are fairly detrimental effects you can surge into as well (literal TPK at low level).  The whole table would probably need to be retuned at that point.  Both good and bad effects would need to be toned down, I feel.  If not it might be a fairly short campaign, but if the idea is a one-shot with lots of hilarity, then go for it... enjoy the CHAOS!