Hey, it's really easy to add send/return effects to single samples in Drum Rack:
On the left side, just under the device on/off switch, click second icon from top(looks like three lines) which will open chain window where you can see all of your loaded samples as well as an area called "Drop Audio effects here" where you can add return effects.
Notice some icons appear on the botton left corner, click little "s" one and now you can adjust your sends for each sample.
But it will work only with drum rack returns, not your main ones.
Also I can say that programming hats with Drum Rack is really easy. Load some hat samples(try to find similar ones but with different "openness") and then place them down. The thing here is like said above is velocity. Introduce some slight velocity changes so that patter is more groovy. Try to go "off grid" in some places. Ableton's groove pool could help with grooves too.
And new function in Live 9, "Drums to Midi" could be helpful too. Try to use it on some not that complicated breaks to see how the groove is created.