First of all, a Herschel Wedge is probably one of the best white light solar filter one could get.
Herschel Wedge can be scaled up easily, you just need a bigger refractor, and it's durable, easy to maintain and safe.
Next, a Baader CaK filter can be used with it, for highest quality results. Then, the Baader CaK can also be used on Venus. So, it means this small piece is both very high quality and very versatile.
Red filters: last night I tried to screw the red filters on my Ranger and also on my Borg 45ED II and they're perfect fit, so now I just need to wait for a good sky to test them. Another local folk has upgraded his PST ot 70mm with a C-ERF which I sold to him a while ago.
He also uses a Meade DS mount, and even a bluetooth aircable serial adapter for remote control.