For wide field I use the Tokina 11-16/2.8. I have the Rokinon 8mm fisheye but have not been doing much night work with it. A wide prime is on my medium list, other items are currently on my short list. I primarily do time lapses with this setup. For non-timelapse astro I'll use anything from a 300/f4L to a 2250/f10 telescope.
The 60Da is a niche camera and not necessary for what the OP wants. In any case, it's cheaper to get a 60D and send it out for modification. Even cheaper to get a T2i/T3i and have it modified. I use a modified 40D and an unmodified 60D.
For a 'tracking mount' solution, I recommend this as a start, it's cost effective and it works:
http://www.telescope.com/Astrophotography/Astrophotography-Solutions/Orion-Adventures-in-Astrophotography-Bundle/pc/-1/c/4/sc/59/p/27154.utsAs for the Polarie, Astrotrac and other similar devices - they work, and work well, but the prices get up into the range of a used CG5 or SkyViewPro mount. The CG5 and SVP come with solid tripods and are designed for greater stability than all but very high end photo tripods. I use a CG5-ASGT for astrophotography with loads up to 20 lbs. I would prefer an even beefier mount but portability is a big issue for me.
Be advised, astrophotography is not a hobby, it's a sickness. It cannot be cured, only treated.......with ever more expensive 'medications'; i.e., cameras, lenses, telescopes, mounts, gizmos, etc. The Affordable Care Act does NOT cover these prescriptions.
I have timelapses at youtube.com/emagowan
Stills including photos of an old telescope mount modified for just what you want to do are at pbase.com/emagowan/astrophotography
The modified mount is an old C8 telescope drive base. Perfect for this application and not too hard to find.