Technique for varying 8th note high hat hits

Here's what I'd do, taking a Hi Hat Tip MIDI note for example.

Amend the MIDI Drum map to reflect 3 channels of this same sound.
Channel 1:  Use this for the notes you want to be stronger and more controlled.  usually the whole, 1/2, or 1/4 beats.
Channel 2:  Use this for about half the notes not being hit on Channel 1.  Then, highlight the entire line of notes and pull the velocity down until it sounds less mechanical.
Channel 3:  Program whatever notes you want that haven't already been programmed in channels 1 or 2.  Then highlight the entire line of notes and change the velocity (don't let it match channel 2). 
 
So if you're playing 16ths on the hi hat, it would be (Channel:)  1323132313231323; stronger hits on the quarter notes, softer on the 16ths, and the 8th notes being somewhere between the two.
Then maybe highlight the entire MIDI clip and randomize a bit.
 
It's more work, but most of it can be done by dragging with a mouse and then mass-changing.  And it usually sounds varied enough to hide the lack of humanity.

I keep all drum midi info on one track. 
With hi-hats, varying the velocity (which should trigger different sample layers) will help a lot. I usually play the part initially, (which also helps a lot.) but end up tweeking the entire kit performance later in piano roll to get as close to "real" as I can. I use a lot of different hi-hat samples. Same goes for snare. Snare and hat require the most work to get "real".
 
For fills, I either play them, or add them manually via piano roll, but I'm careful to not keep every hit on the grid. Drummers usually rush fills a bit. You'll know when it feels right (or wrong.)
 
A little swing or groove quantizing can help as well depending on the groove.
 
Of course if you're banging out EDM with one shot drum samples, then none of this applies. 

timidi
Kind of outdated technology but, you might try playing the part.

my timing on drum taps on a pad or something is all over the map lol

Adjusting velocities in the controller lane is very easy. You can just "chop off" the vertical bars with a swipe of your mouse (button held down) very quickly, so it's a straightforward task to give emphasis to certain notes. I would suggest getting used to editing velocities in the controller lane because it's honestly the quickest way to do it manually. 
 
There are other ways to "humanize" hats which are however not possible in Sonar's piano roll. For instance when I'm editing drums in Geist's step sequencer I can slightly randomize the pitch of each hat hit, or even the sample start time (so that certain hits have slightly less attack). If your drum VST allows fine pitch adjustment you might want to try randomizing it with automation (I think the smart tool has a "random" brush for automation, right?). 

Kamikaze
I'm assuming you have a version with Addictive drums installed. You can drag the midi file into addictive drums.
 
Go to the 'BEATS' section of addictive drums2. Drag the header of the midi file from the track view into the title bar for the beat in Addictive drums (under the green and red play and record icon). Then you can use the Velocity range, accents and random time and velocity controls  in AD2. You can drag it back as a new midi file when you are happy, and drop it onto a track.
 
You could just isolate the hats into a separate midi file first if you just wanted the hats affected.
 
Program straight 8ths rides, with some added sixteenths with the same velocity and drop in AD2. the controls can really add some life into it.   

did not know you could do that. cool way of editing pattern

Not sure how labor intensive this would be compared to what has been posted by others...but, I used to copy and paste my cymbal hi-hat hits in their entirety by creating about 4 measures or more of realistic actual velocity.  Tap on your desk or your thighs and pay attention how you emphasize *all* the notes.  I'd make as many measures of this velocity pattern slightly altered measure by measure, until it became too tedious, then copy and repeat paste that bad boy for the length of the song.  Then go back and throw in fill ins, cymbal hits, ride changes, stuff like that.  
 
Same with fill ins and everything else.  I always tapped it out so I could hear the subtle differences in velocity - not just the obvious emphasis on certain notes, but every single hit and the nature of human performance.  
 
But, honestly, no matter what you do it pretty much sounds like synth drums to me.  I can almost always tell.  If you're just wanting the drums to sound better, then these randomizing techniques are valid.  
 
 

I still find myself using Frank's MIDI plugins for some of these kinds of things: http://www.midiplugins.com/Plugin/12

I've spent a lot of time programming drums, listening/analyzing drums and talking to drummers over the years. Understanding their tendencies helps a lot to create realistic programming.
 
In this case, it is common for a drummer to hit the hat harder and open the hat to varying degrees when playing the kick and the snare. During a fill, or when the drummer moves to the ride... the hat "pedals" on quarters or eighth notes. Actually, sub consciously the drummer is always pedaling the hat... opening and closing it ever so slightly on each hit.
 
The hat is the timekeeper for most drummers... that is why it is continually going. It is also the item "most often on the beat" (aka, in time) while the snare actually drifts ahead and behind the beat depending on the feel. With dance music the kick is usually right on the beat, but in most other styles it drifts similar to the snare to create more feel.
 
There are exceptions to every rule, this is not meant to be a definitive approach - just a generalization.

I've taken to using Jamstix to humanize MIDI drums these days. Given that you can give it your own MIDI patterns to apply "humanity" to, it really does work great for all styles, including electronica and EDM.