The rimming is good, but maybe hardcore analingus can be added. Deep rimming, or drilling, making the subjects body "move" from the force or sensation. 

TL;DR The option to output/inject the pumped milk or cum into themselves or another subject, using a tube as well as connecting it to different toys and SM clothes. DO NOT work in reverse scat and/or urination is not sported in Rack 2.

I already know there will be milking machines similar to Rack 1, hopefully even more. Normally the liquid only gets pumped nowhere, for example in Rack 1 you are not able to do anything whit the produced liquid. I would like to add an opening/tap exit one the pump. Here you are able to connect a tube to, this tube can then be used together with various of toys and SM clothes. When not activated or concocted the pump would operate normally, though when connected and activated the pump will redirect the incoming liquid into the exit tube. The point is that the exit tube can be used on the same subject or another, maybe even multiple subjects?. The toys would be equipped on the end of the tube similar to how you connect dildos on the fuck machine in Rack 1. There should be possible to connect the tube/toys to any of the subjects "hole" (Ass, Vagina and Mouth) as well as the possibility to fix them there. the tube could also be connected to gags and other SM clothes. This would also work very well whit the inflation option. Important to note This is NOT suppose to work in reverse, scat and/or urination is not supported in Rack 2. I am sorry if this has already been suggested before and for any misspelling. 

i think you should add in-game cheats like in rack 1 and allow mod support

If enabled or a d*ck is big enough of a size the "client" should probably choke on it.

A way to implement tentacles without having to spend ages trying to get them to work properly is to make them into a bondage apparatus with the choice to upgrade it for automatic "functions" that could stay on without the player being present.

Said this in a separate post but without proper title  , Options for the facesitting should be updated.

1:Sniff

2:Oral

3:Smother

Give the player manual control of the height of the rack chairs/tables/stocks instead of relaying on the IK.