Sadly, you have picked two cameras that are in different entry level categories. You need to compare the Nikon D5300 with the Canon 700D or the Nikon D3300 with the Canon 1200D When you do that, it could become clear which is capable of producing the highest resolution images if you have the necessary skills. Blurry images tells us that you are using shutter speeds too slow for hand held photography.
Noise, tells us that you are using ISO settings that are too high to produce clean images. Hopefully you are beginning to see that it is your technique using ANY camera that is the problem and even if you spent the money buying a Nikon D810 or Canon 5Ds, your results would probably be the same. When you say your work for a printing company, are you using an offset press and printing four colour images?
How sharp the images appear will have a whole lot to do with the quality of the paper as well as the number of dots per inch each separation has. 180 DPI is about the maximum resolution available when printing on an offset press If on the other hand, you are using a printer like the Epson 3880 or R3000 wide format inkjet printers using pigment ink, then the DPI should be around 300. Any of the above mentioned cameras can certainly produce super sharp images with good colour depth and dynamic range.
Here is a link that shows the quality that can be produced using a 6 mp Nikon D100 (image reduced for posting on the Internet) Here is a link that might help you decide I also think that reading a book called "CYMK 2.0" will provide you with all the information you need to know when it comes to creating photographic prints from a digital image file printed on an offset printer.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.