Knowing very little about the UH (as I favour the SevTec and Otter designs and concepts)-
1.It is perhaps a generally accepted wisdom to----
stick to the plans! IMHO this IS a very good attitude for any craft build, in that the plans -work.
Altering them with the intention of improving a UH does not seem "sensible" (if I can be so blunt)
If a chosen UH needs improving for you to build it--
2 Then why not choose a SevTec as they perform better, exactly as they should, OUT of the box, time and time again.
The only UH I have had the unfortunate experience to be near---was the worst hovercraft both in build (NOT the designers fault!) but in general concept to be a VERY interesting (shocking) hour looking over.
Design of hovercraft has come on in huge leaps since the dark ages of olden times.
I dont know whether UH or Sevs were designed first.
3 I DO KNOW that Barry Palmer (SEV) was an inspired designer, so as such his OLD designs STILL work superbly.
"ARGH- The Laws of Physics canna be ignored " He KNEW his stuff. All genuflect to the West please,,,,
4 As mentioned especially on these hallowed pages--- the aesthetics CAN be improved upon vastly- see Ronnie Legges craft- KERMIT basically a sev but with "pretty clothes"!
Sorry Ron!

visible on various videos in the --video section! Its blue tho, not green but thats another story.
All (as ever) In My Humble Opinion