You’re going to benefit from a dedicated center channel. Large rooms with just basic TV sound are generally horrible. My wife struggled with vocal clarity in our new room until we put in a standard home theatre setup. Since you’re not looking for the highest volume or loudest base, you actually have a lot of options.
Maybe check out the Ascend CMTs. High sensitivity, neutral, decent price. A setup of those with a basic Denon receiver (check accessories4less.com) and you’ll be good to go.
Main 7.1 HT: Dali Zensor (7s, Vokal, and 1s), Emotiva E2s, HSU ULS-15 MK2, Emotiva BasX preamp/amps (MC-700, A-300, A-500)
Kid’s 5.1 HT: Dali Oberon (5s, Vokal), RSL C34Es, HSU VTF-2 MK5, Denon X2400H
7-Zone CCA/Spotify WHA: Paradigm (E-80Rs x6, P-80SM), Def Tech AW6500s, Polk MC-80, Emotiva BasX amps (A-700, A-500), FiiO D3 DACs