scr circuit
Hello,
Are you sure you want to use a SCR. This requires that the current becomes zero.
Looking to your other requirements a H-bridge (4 switches) with a PWM drive, current measuring in the low side switches and EMC filtering is a better option. I don't know the voltage range, but up to several 100V you can buy fully integrated full bridge and half bridge drivers for MOSFET and IGBT (with bootstrap supply so that you can use all N channel devices).
With the correct control loop, you can assure very smooth operation. Regarding the breaking, when the stored energy in the motor's load is very high, you may need dissipators as braking with H-bridges means conversion from mechanical energy to electrical energy. So you supply must be able to accept (store) energy (or you have to dissipate it).
When this is a serious application, you must also think of safety circuits in case of failure of some of the components.