There are many many times when medics have made all the difference. You must be playing it very safe and defensive if you find it more convenient to just respawn at every death.
Yeah medics need to continue to feel like a strong, fun class worth playing. As I mentioned in another thread my suggestion to fix infinite-chain-revives would actually make medics more attractive to me as a class (I rarely play them currently, despite loving assault rifles.) Basically it makes revives instant (less time wasted reviving) but puts a limit on how many instant revives you get in a short time (if you burn through your instant revive charges, you can still revive but it would take a long time, like 5 seconds.) The instant charges would regenerate over time, so your sustained value would gradually replenish back to a maximum. Basically it would both make playing medic more fun, and provide more meaning to killing players. If you kill 5 players with a grenade, sure a medic can just pop each of them (except MAXes) back up immediately with my suggestion, but afterwards each kill you or your team gets won't be able to be revived in a timely manner. So you can actually wear down an enemy force.
