There are many excellent observations here.
But heart of the matter is surely this: the management of these two franchises have, at different times and in different ways, made major errors in both their approaches to selection and team design and, even more so, the selection of their coaching resources. That problematic inheritance is at the heart of these franchises continuing inability to win a commercially viable number of S15 games.
That the Rebels after three years still cannot get defence intensity, consistent application and structures right is simply an indictment of their technical and/or motivational coaching capabilities. There's no excuses for it, the Force in a matter of months under Foley have dramatically improved their defence, clearly demonstrating what's possible with the right instructional skills.
The Tahs' inconsistencies in attack (especially in backs play), and lack of adequate skill and sustained intensity for all of 80 in attack, have been an obvious issue in that franchise for a number of years. In a matter of months, Cheika has made vast improvements in this aspect of Tah capability along with the required improvements in attitude and team motivation essential to a good attacking team mindset.
In Vern Reid, the Force carried a demonstrably poor CEO for far too long (and nearly every year Force crowds fell and keep falling today vs say three years back), and Reid in turn persisted with Mitchell and his odd, eccentric ways for far too long and was obsessed with a team design model based upon 'star recruiting through cash' (vs the type of more substantial and successful model for Aussie S15 team creation followed by (as example) J White, namely find good players with high potential and making them excellent players through superior coaching and people management skill). Then in came the wholly unproven Graham, he left after 10 minutes such was his depth of conviction re his charges, and next, in panic not care, Foley was pulled from NSW after clearly demonstrating severe shortcomings in all of selection, game planning and support coaching staff whilst there all with a far more talented playing stock than existed at the Force.
The ARU failed dismally in its establishment model for the Rebels in terms of the essential calibre of management resources in such a high-risk venture. The franchise is on its 3rd CEO in as many years and how anyone considered it a wise experiment in risk/reward in a hugely tough sports market to give the head coach's job to a Premier grade coach only with zero S15 record is beyond rational comprehension. The Rebels assistant coaches appear out of adequate capability as an aggregated unit as too many core components of game skill are missing, this is wholly forgivable in say years one and perhaps two, but not in year three.
There can be all manner of excuses for a consistently awful w-l % ratios as we see at the Force and Rebels but the fact is that the these franchises' crowd numbers are hovering at potentially life-threatening levels as not enough winning is going on. The ARU's own appalling self-management culminating in its own huge recent losses means there's little cash left for investment in ongoing State RU problem-solving.
Until the total management capability of these franchises is significantly improved, they'll remain predominantly devices for the masochistic enjoyment of a loyal but far from viably sized fan base.