Donny I could be wrong but I think you may find an even trade with a Tyros hard to come by. Someone might not want to trade one piece of gear that is capable of doing the same thing as the two pieces of gear you're trying to trade it for. And even though the A37 Controller KB has 76 keys the Tyros has an Octave switch which accomplishes the same thing although it takes practice to use it seamlessly in a Live situation. The Octave switch feature works with the Tyros' Registrations also. You may find more opportunity for selling the Midjay and Roland A37 Controller KB on eBay and you could possibly get a higher price for them there.
It's worth trying to trade or sell them here but you may find an even trade for a Tyros hard to come by. Especially since the Tyros has 128 note Polyphony versus the Ketron Midjay's ?? polyphony. PS: Ketron doesn't list the polyphony spec for the Midjay but it's highly unlikely it's over 64 notes. Seeing every other board or module they sell is 64 note tops including their top of the line SD1 Plus.
Having said all that I hope you indeed do find a buyer for your gear and acquire a Yamaha Tyros. You won't be disappointed in my opinion.
Especially since the Tyros2 has been reported to have lag time when changing voice banks or voices within a bank and some think the CPU on the Tyros2 has reached it's limit and in fact is past its limit because it does indeed experience a noticeable lag time. Which could raise havoc I would think in a Live situation. Fortunately the Tyros does not exhibit that noticeable lagtime phenomenon. So going with a Tyros instead of a Tyros2 is not only a much less expensive proposition but in my opinion a wise choice.

You will be getting the same polyphony as the Tyros2, the same amount of keys, the same Live! Grand Piano and Live! Warm Grand Piano patches as is on the Tyros2, a better looking design in my opinion, and all for a 'bundle' of money less. And believe me the SA voices are overrated expect in a few instances such as for example the SA Trumpet, the SA Tenor Sax, the SA Solid Guitar, and the SA Concert Strings . But Yamaha is on the right track with the SA voices and I expect them to improve upon the SA realism in the future. But hey! The future's the future and now is now.

It's a great time to buy a Tyros! For all who are interested GC has marked the Tyros down 500 smackeroos from its original purchase price. Negotiate with them and most likely they'll knock down some more. Bargain with them and they might even include some bonus items like a carrying case and/or the Tyros speaker set. But if you don't already own a high end arranger and money is no object then go for a Tyros2. Just beware of its limitations or should I say lag time.
My 2¢
Best regards,
Mike