+1 on the 26/36/48 crankset. You will be able to continue to use your front derailleur as is. You may need a matching bottom bracket to go with the crank but everything else will work.
Attempting to rectify the situation by using an MTB front derailleur to go with an MTB crank will result in a mismatch of Road shifter ratio's and MTB front derailleur ratio's. In addition the derailleur cable arm will probably foul the space between the seat post and the front of the rear tire.