I couldn't give a rats arse whether you keep it or not, why would people want to convice you or even give a crap?
Get a grip man, it's a laptop.
So rude. The guy is asking for help in reaching a conclusion and you think this is an appropriate response? Remember that saying: if you have nothing nice to say, keep your mouth shut...
OP, buyer's remorse is no fun, I feel for you! I think the other's advice of return and re-assess sounds like a good option. Also, don't forget that you have 14 days to return the machine, you can pick up an MBA in the meantime and just return the one that you decide upon. If that's not a feasible option and you still have your old Toshiba, it might be helpful to try using the lower-res display again and seeing how it feels. From a performance standpoint, it's difficult to know how taxing the work the you do really is and whether or not the processor speed / # of cores is very meaningful. Flash games seem like they can run the gamut from simple games like pong to full fledged desktop games taking advantage of 3D hardware.
Good luck!