I played Prince EXO3 Tour 18x20 and found it the softest frame I have tried in the past 2 years. But ball feel is kind of disconnected. I have a difficulty in controlling its power.
Donnay X-Dual Gold 99 is stiffer than EXO3, but still in soft category. Racquet is so fast thru the air, and ball feel is great. Stock weight may be too light. Customization kit can fix the problem.
Pro Kennex Q-Tour is another softer and stable frame. It hits the ball very solid and good control. Ball feel is very plush, but a little sluggish to swing.
DONNAY XP-Dual Pro JB + Weisscannon Dual Reality
Wilson Pro Staff 90 BLX + Solinco Vanquish/Solinco Tour Bite Rough