I am not giving up on the super simple yet but I am looking
at alternatives. One of the best for our application
looks to be the MSD outboard motor 2 cycle type.
Very similar to what Joe Horvath is using for RevMaster.

The 2 cycle engines run up to 7000 RPM and any cylinder
fires once per rev just like a one rotor. Hence two ign. sensors
for a two rotor. One of my neighbors is in the biz of overhauling
out board motors. I'll get some prices next time I see him.

In this case it appears that a single chip microcomputer
like a Picax is the easiest way to control an MSD system.
Resolution of when you fire the capacitor(s) is down to micro
seconds.

To keep it simple and understandable advance and retard
can use the slotted disc mechanical method so nobody has
to learn how to program or tune.

The 300 to 400 volts can still be generated by two coils
in a permanent magnet alternator configuration mounted
on the front of the E-shaft. The ignition coils used could
be the stock 2nd gen E-core coils.

TIME AVAILABLE
RPM..... REV / ... 180 deg.
........ SECOND ... msec.

 500        8.3     60.00
 750       12.5     40.00
 1000      16.7     30.00
 1250      20.8     24.00
 1500      25.0     20.00
 1750      29.2     17.14
 2000      33.3     15.00
 2250      37.5     13.33
 2500      41.7     12.00
 2750      45.8     10.91
 3000      50.0     10.00
 3250      54.2      9.23
 3500      58.3      8.57
 3750      62.5      8.00
 4000      66.7      7.50
 4250      70.8      7.06
 4500      75.0      6.67
 4750      79.2      6.32
 5000      83.3      6.00
 5250      87.5      5.71
 5500      91.7      5.45
 5750      95.8      5.22
 6000     100.0      5.00
 6250     104.2      4.80
 6500     108.3      4.62
 6750     112.5      4.44
 7000     116.7      4.29

This OMC patent pdf makes interesting reading.

Paul Lamar