Need Help Choosing Automation Systems

We just closed on our first home and want to start with best home automation systems from day one rather than retrofitting later. Budget is around $8K. We’re torn between several ecosystems – some friends swear by their setup, others say go completely different. Our priorities are: reliability above all else, wife-acceptance-factor (needs to be intuitive), and ability to expand gradually. We definitely want automated lighting throughout, smart thermostat, and video doorbell to start. Eventually we’ll add motorized blinds, whole-house audio, and maybe irrigation control. The builder is willing to run extra wiring now if we specify what’s needed. Question for the community: is it better to go all-in with one manufacturer’s ecosystem or mix-and-match best-of-breed devices? Also, should we hire an installer now to at least create a master plan even if we phase the actual installation? Really want to avoid costly mistakes that many first-timers make. Thanks in advance!