"Stiff" would describe/indicate the playing (your playing). I don't think that is the case - the playing is "musical" - particularly in the second half.

The loose hi-hat is not a good sound - it does not sit in the mix well at all - and you are, no doubt, really keying on it because you played it (which we all do). I have to say up front (which I have done in this forum a number of times before) - I am not big on high-hats being "noticeable" - I sometimes eliminate them altogether - which is common in modern Country. Your hi-hat sound is "more than noticeable" and the sample itself seems to have a "stiffness" to it - no ring at all - just a kind of "smash" sound... My guess would be that if you found a hi-hat that fits in the mix better (splishier) that you would feel better about it...

Your tom rolls and snare/kick combination later, sound great.

floyd