Hi becky99,
One thing that jumped out at me in your question was
"I want to be able to learn to play real piano stuff. I dont care necessarily about weighted keys as it seems likely that lighter keys will be easier to play"
Personally, you have to come to an understanding here. If you want to play "real piano stuff", you really have got to have full sized, fuly weighter key. You could sacrifice graded action for balanced action with not too much of a loss, but there's a huge trade off if you give up the full sized weighted keys for sure. One of the reasons a piano sounds so good is because the weight of the keys make the instrument so dynamic.
There really is no one board that can do it all, but some come close. Those that do are weighted. Try Yamaha S90 used. I own one and believe it to be one of the best "all-around" boards but it lacks when I need to play fast synth leads or organ palm swipes. It can be expanded but does not contain a sampler for you to load in sound that you've recorded.
But really, you will not learn to play real piano stuff on anything less than full sized weighted keys, in my humble opinion that is. You may want to consider a stage piano like a Yamaha P90 and add a sound module for your synthy stuff ?
best wishes
Bob
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