Solo/orchestral tuniing

I second Keith's recommendations. The Seydel Orchestra S or the Seydel Soloist Pro 12 would probably work well for you. However, they have the solo tuning which means the C notes are side by side where one octave ends and the next begins. (Key notes if the harp is in another key.) I play Asian tremolo and solo tuned chromatics. It took very little practice to be able to switch between the two. Now I play both without any trouble.

The note spacing on the above mentioned harps is different than the tremolo. I can play tremolo and diatonics with no problems adjusting. I enjoy the tremolo harps, but, like you, I do not always want the tremolo sound. Single reeds are better in some cases.

Another suggestion would be to get a chromatic. The spacing is a bit wider, like the tremolo but not identical. Just ignore the button and you have a solo tuned diatonic, but the bends are totally different. Of course, bends are optional since you have that button to get the missing notes. Easttop makes a valveless chromatic called the Forerunner 2.0 which is getting great reviews. I have 2 Easttop chromatics with valves. They are good harps at a good price. I am considering getting the Forerunner 2.0 next because of the great reviews and the sound samples I have heard online. It might even bend like a diatonic since it has no valves, I don't know.

For many years I was bending notes and swapping harps and using alternate tunings to get missing notes. 5 years ago Sarge sold me a Hohner Chrometta. Now I have a Hohner Discovery and 2 Easttops and a Suzuki Chromatix. I should have made the leap years ago. It is nice to have the right note at the push of a button. Chromatics are not good for chord playing, in my opinion, but they are great for following the melody exactly.

Good point, Keith. It would probably be an excellent choice for someone who wants a solo tuned diatonic. No valves. The chromatic ability would be a bonus feature.