Connections

I think as long as all consecutive slopes have opposite direction, the Bluetooth mode will work well.
However, the Bluetooth mode still offers advantages. Example, in Wifi mode, if you want to loop a video you will have big sluttering with each loop. In Bluetooth mode this sluttering also exists but in smaller so they will be less perceptible.
It's only possible to adjust the playback rate in Bluetooth mode. No need to upload funscript and a big list of devices are only bluetooth. 

Wifi :

• More accurate and allow to play more complexe funscript

• Only compatible with TheHandy

• The device need to be synchronised with the server and the time offset between the PC and the divice must be calculate

• Need to upload funscript each time you want to play new media

• Big sluttering in loop mode

• Impossible to change the playback rate

Bluetooth :

• Less accurate

• Compatible with many masturbator (See the list of all compatible devices with Buttplug.IO that I use for the Bluetooth)

• No synchronisation needed

• No need to upload

• Small sluttering in loop mode

• Possible to change to playback rate

Personaly, I use Wifi to play with my masturbator but I will need Bluetooth when I will add the HMV mode.
Also, you can use two masturbator at the same time, one in Bluetooth mode and the other in Wifi mode. I neever try that but I made my coding to make that possible. Let me know your impressions if you try.