The one on there now is a single pivot caliper which is as flexy as a flexy thing. I wonder if a dual pivot caliper would make any noticeable difference? The reach is just about at the limit of its adjustment on this one. I suspect that a longer reach brake, with the blocks in the middle range of its adjustment, might feel stiffer due to the more effective leverages involved. I will see how things go with with my recent modifications first, before making any further changes, based on the principle of just changing one parameter at a time and evaluating the result. I still have some Clarks blocks to put on once I have got the current set up as good as I can get it.Dia-Compe ‘Big Dog’, beloved of the old skool BMX fraternity was the standard fit for a while. Can’t tell from memory, and the pic, but it was a dual pivot side-pull.
My Linear is decidedly tail heavy, and with a full rack bag has a tendency to flip if the front wheel is lifted with no rider aboard, to turn it in the garage for example. I recently replaced the (temporary) aluminium prop stand leg with a steel one but really need to put the prop stand clamp further back now I am using it in earnest.If your prop stand is towards the rear of the bike, and strong enough, you can tilt it to be supported on the stand and the front wheel with the rear off the ground... alternate turning the pedals and adjusting the gears and you can change whilst stationary. Works on my Fuego.
I would also observe that I find my Recycled Recumbent easier on the rough roads with a passive suspension effect over that long wheelbase than my Fuego, even with its rear suspension.