Originally Posted by 2manybikes

What the shop did was replace the derailleur hanger. It is a separate part and it protects the bike by being replaceable. It did it's job.

Sounds like possibly a perception problem. Do you pedal gently when shifting gears?
It does take a little time for the chain to move over to the next cog. When shifting the pedals need to be turning but very little pressure on them. One also does not shift going up hills, because of the pressure on the pedals. One shifts before the hill. being in a gear where you can pedals at a relatively high speed, with not much pressure on the pedals will speed up shifting time.

If it shifts properly, as already mentioned, the derailleur problem is fixed. Harder on the legs could just be perception or an unrelated problem like low tire pressure.