Transmission either delays shifting or the rpms go very high before shifting

Sounds like possible slippage and other transmission strategy issues are present. This can't be figured without proper diagnostic testing using diagnostic equipment to monitor shift points, commands and the reaction of shift solenoids, relative to actual performance. Seek guidance from a local shop near you. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops