Driver spacing advise for EXOTIC synergy/ MEH horn

[Korppi]

I have Apogee Duetta speakers,see the attachment

In my Duettas bass foils are broken, thinner ribbon plays the highs

In my Duettas high ribbons are ok

Original crossover was 500hz at 6db/oct

Ribbon for the highs plays better, last longer, if its crossed steep at 1khz

I dont like these style dipole speakers, too many variables with interaction with the room

So i want to make the highs ribbon part directive, narrow directivity and close the back

The high Ribbon is 1,3 meters long and i am wondering about cone driver spacing if i make synergy horn

So plan is to make two way tall synergy horn and play with cone drivers from 200hz to 800hz/1khz
And from ~ 1khz the ribbon can take over

I have 15 inch bass bins that can play 30hz to ~ 200hz.

In a normal synergy horns midrange driver spacing is pretty straight forward...

if i place the cone drivers same way as in normal synergy/meh, its a lot of drivers 🙃 3 inch cone drivers divided to both side, 1.3m tall....

Some people have repaired apogees by replacing the bass foils with cone drivers, see the attachment

So some ideas:

Red circles are the cone drivers placing examples in the pics, idea1, 2, 3...
.. unlike on the pic from the ribbon horn idea, the horn is of course closed from top & bottom, made to a horn

1) make a horn for the high ribbon only, close the back.
Use repaired style cone drivers from 200hz to ~ 800hz. Cone drivers without a horns

2) make synergy horn, like mentioned before, lots of drivers needed

3) make synergy horn with wide cone driver spacing

4) make synergy horn so that the cone drivers are only in the middle of the 1,3m tall ribbon, at the level of listening position

Any comments and advises welcome!