[Elecraft] Clever antenna tuning ideas wanted

[Vic K2VCO]

OK, here is what I want to do:

I have a 33' (10m) vertical with the base about 10' (3.3m) above ground. 
  It has four 8' (2.4m) radials which are connected to the feedpoint 
through a coil which resonates the system on 7 MHz.  It works as well or 
better than any vertical that I've used on 40m -- low SWR and good 
results.  It's fed through a relatively short (20', 6m) length of RG-213.

I would like to use it on 80m and 30m as well.  My first try was to 
simply use the KAT100 to tune it.  It tunes fine on both bands (1:1 at 
the rig), but results are fair-to-poor on 30 and poor-to-worthless on 80.

On 30m, the coax losses are reasonable (the SWR on the coax is about 8 
to 1, but it's very short).  I suspect the problem is that the radial 
ground system is very poor on this band (on the other hand, the long 
vertical radiator should provide a slight amount of gain).  So I may try 
paralleling a set of radials tuned for 30m.  They will also be short, 
but resonated with a coil or stub.  Does this sound like a good 
analysis/solution?

On 80m, it's more complicated.  The ground system is terrible, the 
radiation resistance of the vertical very low, and the SWR and losses on 
the coax very high.  No wonder it's a dummy load!  I guess the way to 
deal with it is to add more tuned radials in parallel and a switchable 
base network, but I would like to avoid any more control wires that have 
to go through my lightning suppression panel (I can't pass DC through 
the coax, either).  Does anyone have any suggestions?

-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco