My first TrueNAS homelab was based on an Athlon 3000G and 16GB of RAM. And I ran Nextcloud, Home Assistant, and multiple other services with globaly no ptoblem. Your configuration should be OK.
It’d be easier to stick to Truecharts. But I can’t tell for community plugins, never tried them.
Do not use that 1To SSD as boot drive, it won’t improve anything over the 250GB SSD. Use the later, maybe buy a second one to make it redundant. Then use the 1 TB SSD for an Apps pool, and the HDD as a single RaidZ2 array for all your important datas.
Thank you for the information, now I can block you without having to worry about missing anything of interest.