I'd replicate the advice/sentiment shared already and forego a center channel. If ever that route would have to be taken the only true solution would be 3 equal front speakers, period, but then you'd need a perforated screen + projector for that to make any sense.
What I would do instead, and that wouldn't only serve Home Theater duties, is investing in a massively capable sub set-up, which is to say loads of displacement, headroom and no less than 20-25Hz extension (some may say honest 15Hz is required for HT to cover most, as in 99% of the infra-sonics found on the many Blu-ray/4K UHD titles, but a lower tune impacts the overall sensation of the bass - i.e. central to upper bass, and hereby integration in particular - so it's a compromise). This is MANDATORY for movies, but properly integrated (which goes without saying) will serve music reproduction as well.
As for the particular sub solution (and ULF capabilities) to choose here, I'd forget about über-expensive subs and instead amp up their number for a DBA sub set-up, or go with 2 very large ones. If acoustic live performances are very much your cup of tea and form a reference for your home audio reproduction, I'd place the subs (say, 2 or 4 of them) symmetrical to the mains and coupled in stereo. If not a mono-coupled DBA placed asymmetrically may float your boat. Either way, never skimp on displacement and headroom, and get sufficient extension.
What I would do instead, and that wouldn't only serve Home Theater duties, is investing in a massively capable sub set-up, which is to say loads of displacement, headroom and no less than 20-25Hz extension (some may say honest 15Hz is required for HT to cover most, as in 99% of the infra-sonics found on the many Blu-ray/4K UHD titles, but a lower tune impacts the overall sensation of the bass - i.e. central to upper bass, and hereby integration in particular - so it's a compromise). This is MANDATORY for movies, but properly integrated (which goes without saying) will serve music reproduction as well.
As for the particular sub solution (and ULF capabilities) to choose here, I'd forget about über-expensive subs and instead amp up their number for a DBA sub set-up, or go with 2 very large ones. If acoustic live performances are very much your cup of tea and form a reference for your home audio reproduction, I'd place the subs (say, 2 or 4 of them) symmetrical to the mains and coupled in stereo. If not a mono-coupled DBA placed asymmetrically may float your boat. Either way, never skimp on displacement and headroom, and get sufficient extension.