Some Questions About Raw from a Newbie

Hi everyone! I'm new to this site, as well as new to feeding raw, but after a lot of research I feel like it's best for my fur baby. From what I've understood, the raw mixture should be 80% meat, 10% bone, and 10% organs plus supplements. My question is, what would happen if the ratio was 70% meat and 20% bone instead? Will the bone content have negative effects on my cat? I plan on buying commercial raw until I invest in a proper grinder (it's hell and half to find a good one in Canada) and from the limited options I'm seeing, 70:20:10 seems to be the most common ratio. Also, are the hearts a part of the organ percentage or the meat percentage? That could be something I have to contact the supplier about... 

And one last question: I would be getting the ground meat frozen, but I have to add supplements to it before I can feed it to her, is it okay to thaw the mixture, add the supplements, portion, and then refreeze? Thank you all for taking the time to read this! 

Welcome to The Raw Side and The Cat Site.
You're right, 80/10/10 is the recommended percentage to start with. 20% bone is probably too much--too much bone can cause constipation. I fed Ritz 7% bone--any more than that and she gets constipated.
Hearts are considered meat/protein, as are gizzards.
Regarding 10% organs, at least 5% should be liver.
Supplements: yes, it is okay to thaw the mixture (but just enough to add the supplements) and then add the supplements. Where are you getting your ground meat? Ground meat can be problematic depending on how sanitary the conditions are where it is ground and how quickly it is frozen. Personally I wouldn't buy ground meat from the grocery store.

Ritz has covered some good points.

I like to think of the raw ratio as 80-10-5-5, since liver is essentially its own category.  And yes, hearts and gizzards are muscles so they fit in the 80% portion.

Personally, I've never fed commercial raw (I feed prey model style), but from what I've read many of them are a bit heavy on bone.  Sophie1 outlined a good way to add in a little extra meat to modify the bone levels in commercial foods in another thread.

You haven't mentioned if you have already begun feeding raw, or are in transition.  Assuming the latter, remember to be patient with yourself as well as kitty.  Everyone has a different experience.  Some transitions go super smooth; kitties jump right in and will eat everything in front of them.  Others take more time and patience as kitty's system adjusts to the new food and you discover their likes/dislikes. 

We have a lot of great folks here, ready to answer questions as you set out on this new road. 

I'm actually getting my ground meat from a raw food pet boutique in Toronto. Unfortunately they cater mostly to dogs but they have a limited selection of raw cat foods as well. As I was browsing through though I noticed that even a lot of their cat food had a 70:10:10 ratio and that didn't seem in line with the research I did. 

I haven't started feeding her raw yet. It's been a long transition to get her from all kibble to all canned. Now I'm trying to get her on a more consistent feeding schedule before we embark on the canned to raw journey.

I will definitely check out that other thread! It may come down to having to add more meat to kind of balance it out. The ultimate goal is to buy a grinder and make her food myself, but until I have her transitioned fully, I'd rather stick to the 'ready made' raw as opposed to spending hours in the kitchen grinding up her meals only to have her sniff it and strut away. I don't think my hear could take that.