Here is what I think the problam is for the G940 in IL2 and LOFC. I'm going to start with IL2 as I feel it really provides the best example of what I think the problem is.
In IL2 on take off you can feel shudder in the stick with the stick at centrepoint, which shows that forces are effective and being transmitted to the stick.
After take off the stick goes completely loose at the centre around 20% of the throw travel, in x and y, from centre is met with no resistance. At 20% resistance is felt which I'm assuming is the FF effect of the control surfaces feeling wind resistance. This resistance increases with further stick throw as would be expected.
The problem to my mind (and I'm probably wrong) is that there is no mechanical resistance data for the centre point. The pilot would experience mechanical resistance in the flight controls at low deflection due to friction in pulley/geared systems in old aircraft which is not being modelled or if it is it is far far to weak.
In LOFC there are no "hollywood" FF effects. The stick simply moves to reflect the trim state and generates resistance at higher deflection but there is still about 20% with no resistance to movement
In newer aircraft like the Su25T which have hydraulics there would have to be a centre spring/gearing or some kind of mechanical resistance to stop unintentional stick movement as there would be no real resistance from the stick as its not directly attached to the control surfaces.
In both cases i think weak centre spring data or lack of center spring data is causing the slop.