Hard Hitting/loud Drums without overloading?

Basically, judicious use of EQ and compression. Compression alone won't automatically make the drums big. You have to figure out what frequencies you want the kick and snare to sit in and reserve that space for them. A good compressor will allow you to change the shape of the drum sound by altering its transients and bringing out the sound of the drum itself. Then you use EQ to remove the frequencies that you don't want to hear. This will emphasize the frequencies you want to keep.
 
Don't put any reverb on your drums until you are happy with the sound dry.
 
To apply an effect to a part of a clip, use automation to dial the effect in or out as needed. You can also create a send, place the effect there and automate the send level.
 
Of course, all of this advice assumes you can hear what you are doing. You'll need good monitors and a proper mixing environment as well.
 
Hope this helps a bit. There are lots of books on mixing that can really help. I would recommend "Mixing Secrets" by Mike Senior. It is a very accessible read.
 
Regards,
Dan
 

Just a few more ideas that may also potentially help in this case. Many important ones have already been covered.
 
Some people think that kick and bass should always be below a certain frequency.This is often not true. If you've ever listened to a great mix heard from  a low end speaker with little bass you can still hear the transient from the bass drum because the mixer isolated elements of it that were higher in the EQ spectrum. Accentuating that portion of the kick and boosting it slightly in higher ranges sometimes helps.
 
If you find that there are  other parts conflicting with the kick you could apply a slight amount of side chain compression to the opposing parts.This would be a last resort over making room with EQ and other measures.
 
As you build a mix you will find that there is a cumulative effect in track gain stages. If at the beginning of the mix a track seemed ok, but after adding several plugs with gain or when you add a  mastering plug-in everything is crazy loud...it's probably time to pull everything back down and re adjust gains.Some mixers stay at -6db or less in all beginning tracks. This is usually a rule of thumb I use to start and I still need to back off of things.

What are you using for drums?  What do you mean by big and hard hitting?  Give some examples of drums that sound like what you're trying to achieve.  I don't know if MC6T has the same capabilities as Sonar as far as bussing goes but here's what I do in Sonar:
 
To me, there's a difference between "Loud" and "Big."  Drums don't have to be loud to sound huge--and conversely loud drums aren't always huge (punk drums are loud, but aren't usually huge.  Prog rock drums aren't always loud but are usually huge).  
 
In my opinion, big drums are created in a big room with a really good and well-tuned drumkit; if I have the luxury I'll book time in a good studio to get that sound. Since I don't always have a budget and I don't have a huge room of my own I close mic the entire kit and try to suppress as much of the ugliness of my room as possible.  After recording I start by bussing my drum tracks.  I create a buss for two kick mics (beater and outside); two snare mics (top and bottom), the toms, and the overheads--I don't always use both kick drum mics or both snare mics, but it's nice to have them.  
 
Once I get the individual drum tracks tweaked (if needed: EQ, compression, etc.) to where they're sounding decent, I turn to the busses to adjust the levels between them.  Each buss is then sent to an "everything buss" so I have one place to control the level of the entire kit.  This everything buss has a send to a buss with a good reverb (usually a room simulation since my tracks are really dry)--I like doing it this way instead of in the drum buss' FX bin because I'll sometimes send other instruments to this same reverb buss to put them in the same room--sometimes I'll just send the individual drum busses instead of the everything buss to the reverb buss, for instance if I don't want a lot of "room" sound on the kick.  If they're still not big enough, send the drum buss and the reverb buss to a buss with some seriously heavy compression on it.  You'll have to fine tune the levels on these busses to suit your song.  
Even when I'm not using a live drummer, I have a track dedicated to each part of the drum kit (kick, snare, toms, cymbals/overheads, room).  Then I do pretty much the same thing i described previously (I tend to use samples that have an option to turn on or off the room mics).
 
This is like a 30,000 foot view of the way I do drums--an overview.  It's kind of pointless to go into the details about it since my drums and recordings are probably very different from what you're working with.  Also, I'm not a drummer.

Rimshot

bitflipper
I had a teacher in grade school who liked to get everyone's attention by smacking a ruler on his desk. It would make everyone jump - unless the class was making so much noise that the ruler-smack got lost in the din. Even though it was just as loud as always, it lost its impact because it was no longer loud relative to the sounds it had to compete against. In mixing terms, the peak-to-average ratio (also known as "crest factor") was too low. 
 
Loudness and punch are relative. For example, a drum hit is impactful only if it rises significantly above everything around it, including its own sustain. IOW, how hot it is relative to everything else. 
 
Trying to make everything loud makes nothing loud. If loud drums are paramount, then you have to be prepared to sacrifice other instruments toward that end. 
 
Plugins such as Rough Rider can actually work against you in this regard. They'll make drums sound fatter, but at a cost: namely, flattening out each hit so it no longer rises as far above the surrounding sound. The consequence is reduced punch. A big part of mixing drums, and indeed all mixing, is finding a balance between peak and average levels. Rough Rider lowers the crest factor by raising average levels while lowering peaks. 
 
 
The kick is especially challenging, because we simply don't hear low frequencies well. It takes a whole lot more energy to make low frequencies sound loud. This is why many mixers start with the kick and reference everything else to it. You can't just keep turning the kick up when it starts to disappear into the mix, or you'll end up right where you are now, with no headroom left.
 
Try applying the compressor to just the kick rather than the whole kit, then adjust the rest of the kit accordingly. If the kick starts to disappear, don't raise it - lower everything else.
 
As for the second part of your question, the answer is automation. Presumably you're using a synthesizer for the bass; the wobble is amplitude modulation and can be automated to come in exactly when you want it to, and how quickly. The exact instructions for doing this will depend on the synth, but any synth that has a knob for adjusting the modulation amount can be so automated.

+1
 

Yep, saved me a thumb callous, did Mr. Bit.