Best place to start with improvements is a more substantial grinding rest. The supplied sheet metal type aren’t really rigid enough for confident grinding of tools.
Here is one I welded up from 6 mm and 10 mm steel bar to replace a missing part on a Creusen grinder by almost replicating the remaining one.

Not difficult to make if you have milling facilities. PM me if you’d like pdf copy of the drawings. Obviously you’d have to re-dimension for your grinder.
The Creusen has a bar for the rest to ride on with one locking knob on a fixed stud. I think thats a more secure mounting than the two bolts in slot system on the Draper. Certainly easy to adjust. Relatively simple modification using countersunk screws, preferably hex socket, in the existing holes to retain the bar.
The various versions of the Hart style grinding rest are undoubtably more versatile but I’ve never really felt the need. Although on my previous grinder I used this :-

from Aximinster tools as a cheapskate substitute working against the side of a cup wheel pending building the proper thing. Which never seemed to happen despite serious temptation from Harold Halls excellent, simple to make, design with its versatile set of accessories. In all honesty that Axminster device was a bit marginal when it comes to stability. It never troubled me, probably because I was always aware of the need for appropriate care.
Clive