First, they'll need a high-speed charging network that will allow for long-distance road trips. Public charging infrastructure is too slow to realistically allow for a trip that is further than what one can do on a single charge. Granted, with 200 miles instead of 40, this is significantly better than what's out there now, it's still not good enough for someone that wants to occasionally take their car on a multi-state road trip. Tesla's supercharger network gives them a competitive advantage, and GM will need something similar. Tesla has said that they are willing to share access, but it has to be on their terms. If GM is willing to buy in on that, we might see a Bolt capable of using Tesla superchargers - this would solve this issue for GM.
Second, the established dealer network has no interest in selling EV's. Most of their profits come from after-market service, and EV's have (theoretically) significantly less service needs. To this end, the dealers are motivated to push traditional ICE's over EV's in virtually every case. This is the major reason why Tesla does not use the traditional dealership sales model. No car salesman will direct you to a Bolt - you'll only get one if you come in specifically wanting one and push past their sales tactics to get you into something else. Buyers of the Nissan Leaf have reported resistance to and sometimes outright hostility from dealerships over wanting to purchase an EV. Unless GM is somehow able to break the dealership cartel and begin direct sales themselves, this issue won't be overcome anytime soon.
Another thought: at $30,000, I strongly suspect it is priced as a loss-leader, meaning it is being sold under cost. Tesla needs the economies of scale of their massive battery factory they call their "gigafactory" now under construction in Nevada in order to achieve a $35,000 price point for the Model 3. It seems unlikely to me that GM has managed to bring the cost down so much without a gigafactory of their own. It seems likely to me that the Model 3, at $5000 more expensive, will be superior to the Bolt in virtually every respect (Tesla has repeatedly said that their 200 mile range will be a real-world figure, while the Bolt's 200 mile range will probably be an ideal figure in perfect conditions, though I'd love to be proven wrong about the Bolt).
All this assumes that GM actually delivers as promised, which is far from guaranteed.
That said, more competition in the EV space is a good thing, so I hope the Bolt does at least well enough for GM to continue research in the area.