TBE when RTH in a Hover

[PilotHal]

So, I dialed up my gains as per recommendations. I'm flying a F550 with 8x5 Graupners and the stock motors, with a H3-2D gimbal, and a 6600mAh 4S flat pack battery.
Pitch. Roll. Yaw. Vertical.
Basic. 210. 210. 110. 137
Attitude 175 175

60% Expo on AIL/ELEV/RUD

When the multi comes back via RTH/FailSafe, it hovers and there is supreme toilet bowl effect.
Any ideas? The CG is very good. I did move the GPS antenna from the rear of the top plate to the center. Do I have to recalibrate the compass?
Should I go with bigger props?
Thanks!

 

[Benjamin Kenobi]

Yes and yes! Always recalibrate the GPS if you move it or make significant changes to your setup. I think you should up prop size a bit with the weight of the gimbal and a large lipo. 9" Graupners or possibly 10".

Cool?

 

[PilotHal]

Cool.
Now, which props to use... I think I am going to order 9" Graupners and try those to see how it flies. Will that impact my flight time? Is there anything else I need to worry about?