Clutch vs. Clutchless

This question has 2 angles. One is drivability and the other cost.

Drivability:
In an ICE, the clutch is used to allow the engine to idle and to bring the vehicle up to speed in 1st gear. Since in an electric motor the RPM is variable from 0 up to around 5000 the clutch is not necessary. So drivability is only about shifting from 2nd to 3rd etc without a clutch. Many cars are really smooth shifting, especially Honda's. Our current Toyota corolla wagon is pretty rough shifting so it wouldn't be fun to repeately shift without a clutch. It takes a few seconds longer to get the gears to mesh.

Cost:
The question of cost and conversion simplicity is a no brainer. With a clutch, the flywheel, clutch and pressure plate are kept in place. This requires a coupler between the flywheel and e. motor shaft. It also requires that the position of the flywheel and the alignment of the e.motor shaft and the drive shaft be maintained. So, in my case using a flat piece of aluminum for the adapter plate required the flywheel to be machined down. The flywheel weight loss was good, but took a couple hours of machine time. The alignment of the coupler and the driveshaft was pretty critical too. This required an additional 4-6 hours of machining.

No clutch:
Another way to handle this would be to use two lovejoy jaw couplers (grainger.com)... the way they were intended. One would have a 1.125 inch keyed shaft for the electric motor and the other would have a splined shaft to match the spline on the drive shaft (in the car). The flywheel, clutch, and pressure plate would be removed completely. The adapter plate would be flat and the shaft alignment not as critical because the jaw couplers have a separator between them that gives a little, 1-2 degrees. So, you could almost hack together an adapter plate and the couplers would cost you $14-$26 each depending on your HP and the divider is about the same price. So for around $80 you could have a coupler. Matching the spline would be the trick, but should be possible.