I wouldn't want to shoot looking at a 10x magnification. 5x view is just about useable but is still only around 50% of the captured frame size(=2.475x at 1080p dimensions).
Aliasing and moire seem to be getting confused here. The 50D will alias (sometimes badly) in non-crop but is much less in 1:1 crop mode and totally down to pixel size. Moire is rare in crop mode but can happen. Hey, even the ARRI Alexa suffers from it

Moire can only be totally defeated with a huge increase in pixels and a reduction in pixel size but this also has a knock-on effect to low light performance.
Excessive moire can also be down to how you process the DNG files. For extreme cases you really need to use AMaZE debayering (as found in Raw Therapee) or the anti-moire tool in ACR. Aliasing is more difficult to treat. I've tried anti-aliasing plugins but they have minimal positive effect. The only '
ok but not perfect' solution I have found when trying to rescue a 50D shot with bad aliasing is some serious post work, rescaling up to 4k or larger and back to 1080p. This softens the image but reduces aliasing artifacts. You then need to add selective sharpening to enhance areas that are less prone to aliasing and possibly add blur or even do some matte paining to artificially correct a scene. It's a lot of hassle if you're only shooting for fun.
That said, I've found the 50D is actually better than the 7D (which has FPN problems) for raw video and it can just about match the Bolex D16 image. The Black magic Cameras are significantly better but obviously much more expensive than our 5yr old DSLR.
After using 50D raw video for the past 9 months I would offer the following advice:
1) remember the limits of what you are shooting with. Don't expect night vision or 5D Mark III quality. The 50D is somewhere between an S16 and S35 but behaves like Super 16. It has +/- 11 stops of DR (Dx0 tests) but in reality only about 9-10 without excessive noise. However, noise can be cleaned up with Neat Video and can be squeaky clean but retain detail at ISO 1600 with the right settings (i.e. temporal filtering and only reducing noise in the channels that actually have noise).
2) The 50D needs light! It will give exceptional results (considering it's age) if you remember this.
3) Post processing is important. You're shooting raw video so why skimp? If you want fast and easy then shoot H.264 (or, pardon the plug, use Cinelog and a LUT

). It takes some careful steps to even get to a good starting point for grading but it's worth it.
I'll hazard a guess that no matter how bad your shot is, it can probably be cleaned up if you use the appropriate tools for the job but ask yourself first 'is the shot is worth saving?'! Sometimes a re-shoot, after learning how and where aliasing/moire occur in a given situation, is a better option.