I would love to see a larger RISE. A 61 or even 88 keywave RISE!
My speculation is part of why it hasn't been done yet is some overlap with the GRAND range's keys (those still have a strength insofar as a built-in sound engine so they can be played standalone without a computer), but time will tell...
While a larger Seaboard than my 49 would be great, in my setup (of three keyboards, the lowest being a VPC 1) I in fact could do a an octave peal for the Seaboard by installing an appropriate Mid preprocessing script, which is rather easy to do in Reaper.
Guys, the reason seaboard has gotten smaller year after year (from the first Grand to the Blocks we have today) is that so many Keys are not needed in modern electronic music. I understand your wish, as a piano player myself, but trust me... I have a SR49 and I regret i didn't go for the 25 because this little gem of hardware excels at creating textures and you don't need a full sized keybed for that ; for solos you have the octave switcher which requires little practice to work with so you're pretty much covered. Then I understand everybody has his own needs but more than 49 is just gimmicky in my modest hopinion (and Roli knows that)
Yes please! You could connect several blocks together but each block must be charged separately and if You want a sustain pedal it's not just to plug it in.
Maybe a similar solution as with Blocks could work - make a new Rise with 36 or 48 waves and attachable Rise blocks with 24 waves. Then You can easily archive 3-5-7 octaves (or 4-6-8 octaves). The attachable Blocks would not need any batteries to keep the cost down.
I vote for a connectable standalone 5D 88 keys getting the best of Rise & Grand, I'm pretty sure you'd get easily financed in no time through an online funding campain... just saying ^^