In the almost 40 years (wow, I just did the math and it really has been that long) that I've been a gigging musician, the majority has been as a keyboard player. There is a big difference between a "piano player" and a "keyboard player". This guy may not know that and how a keyboard needs to fit in a band. Unless there's a signature left hand lick, there's not a lot of work down below E3 (the E below middle C). There's a reason rock organists started leaving the pedals to their B-3s at home. And you have to watch your chord voicings and inversions. A lot of times, piano-turned-keyboard players will try too hard to be technical and try to play full "correct and proper" chords when they're not needed and will clash with the voicings the guitarist(s) play. If the guy's willing to put forth the effort, there may be hope. Talk with him about it. If he doesn't grasp what is needed, let him go.
As for the guy's "cheap" Yamaha and its lack of appropriate and/or needed tones (Rhodes, Wurly, Hammond), Yamaha makes several really good (and some not so cheap) digital pianos that don't have all the bells and whistles. My bottom keyboard these days is a Yammie P35 I bought from GC for $250. I use it for mostly for its acoustic piano sound. Nice weighted action and it weighs half of what my old Korg SP250 weighed and cost a fourth as much. My top keyboard these days is a Casio WK7600 (yes, a $500 Casio!). IMHO, it has very convincing Hammond tones (I own a Hammond M100 and an H100, and have played various A's, B's and C's) complete with 9 sliders that act as drawbars and a Leslie sim that ramps up and down well enough, although the fast speed might be a little too fast. The strings, brass, and woodwinds are very realistic sounding. The other sounds will get you through gigs if you need them. The keyboard has a decent enough synth-type action. It's durable enough to handle my heavy Jerry Lee Lewis when put into piano service (back in the 80's, American Music here in Jax used to keep replacement keys in stock for our band's Yammie PF10 because I'd routinely break them; our BL was stuck on the sound of that board for some reason) and has held up to Hammond glissandi without any issues.
As for the guy's "cheap" Yamaha and its lack of appropriate and/or needed tones (Rhodes, Wurly, Hammond), Yamaha makes several really good (and some not so cheap) digital pianos that don't have all the bells and whistles. My bottom keyboard these days is a Yammie P35 I bought from GC for $250. I use it for mostly for its acoustic piano sound. Nice weighted action and it weighs half of what my old Korg SP250 weighed and cost a fourth as much. My top keyboard these days is a Casio WK7600 (yes, a $500 Casio!). IMHO, it has very convincing Hammond tones (I own a Hammond M100 and an H100, and have played various A's, B's and C's) complete with 9 sliders that act as drawbars and a Leslie sim that ramps up and down well enough, although the fast speed might be a little too fast. The strings, brass, and woodwinds are very realistic sounding. The other sounds will get you through gigs if you need them. The keyboard has a decent enough synth-type action. It's durable enough to handle my heavy Jerry Lee Lewis when put into piano service (back in the 80's, American Music here in Jax used to keep replacement keys in stock for our band's Yammie PF10 because I'd routinely break them; our BL was stuck on the sound of that board for some reason) and has held up to Hammond glissandi without any issues.
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