Go for it! That would be the ideal installation, if you are up to building the platform. Either way, rubber isolators are must, whether you place them on the platform, or on the chairs themself if you do a direct mount. I ended up buying 30 isolators for my 4 recliners.

If you do choose to cross over your transducers at a lower frequency than the subs, you can either utilize a buttkicker amp that already has the variable crossover in the unit, or buy an FMOD high-pass filter from parts express (I believe it runs at 50hz).