Check out the Hermes Lite, it's an SDR with a transmit ability, and some other additional features. I think it's 10w by default, but a lot of people put that right into an amp to get up to 100+ watts.
I hand build a few of the early prototypes and have a couple of the production versions too. I cannot emphasize how underrepresented I think this radio is compared to a lot of the other SDR hardware out there. It compares favorably in performance and vastly exceeds the features of most amateur radio HF transceivers in the <= $2500 range.
Because it speaks the OpenHPSDR protocol it can also run a digital predistortion algorithm called PureSignal that samples the PA output and distorts the input signal to correct for amplifier phase and power nonlinearity. Digital predistortion is relatively common in modern radios like cellular baseband, but to my knowledge PureSignal is the only open source implementation of such and the only implementation publicly available for an HF radio.