I think the Hydrasynth is great... the interface is perfectly OK to navigate with the Module buttons, screen and encoder knobs. The modules have 1-3 pages of parameters each, so not too much menu diving needed there.
The Mod Matrix and the Macro buttons though... require quite some menu diving if you want to make the most of 'em. And it gets hard to keep track of all the modulations you've set up... which can cause confusion, like unknowingly double-patching stuff, which happened to me.
So, to make things easier I made an editor on the TB Midi Stuff app. It has a few drawbacks though... ASM used the same NRPN address for BOTH source and destination on the Hydra, source values 0-127 & 256-311, destination values 128-255 & 312-439. This causes confusion for TBMS, ie when choosing a mod Destination on the Hydra, the TBMS may pick up jibberish and change the Source as well.
Because of this, I had to make the Source and Destination pick-lists uni-directional, that is the TBMS app won't pick up if you set up Mod Matrix Sources and Destinations on the Hydrasynth. TBMS does send that data when you choose Source and Destination though. Same goes for the Macro Destinations.
The sliders and knobs are all bi-directional however, which means they work "both ways". TBMS picks up what happens on the Hydra regarding these, and vice versa. So in a sense this is strictly a "substitute" to setting up modulation routings, sources and destinations. The benefit is to have everything readily visible and for adjustments when making very complex patches.
Whenever you're done editing a patch, you have to save the page as a "Canvas Snapshot". Click on the magnifying glass, top left corner, then click on the 'I' by the name, rename to fit patch name, and save as a new Canvas Snapshot.