That Flying Monkey, he can more than hack it, you know.
Actually FM I'd add that you probably would have found MM hard going from a technical point of view, rather than a fitness point of view. In all seriousness I'd suggest that you get more trail experience if you're going to do more endurance events next year. You're perfectly placed to go up to the borders, all you need is a cycling friend with a car, who also mtbs (in theory). Guess who I'm talking about...
I have no idea about tyres for Catton but it is pretty flat. There's a bombhole in it somewhere, and a watersplash, and some nice singletrack. It's west midlands mud, which doesn't contain too much clay. So you'll be fine on a regular XC tyre unless its very very very wet.
The Kenda was alright this year. Ironically enough people were searching for grip on the grass, not the mud part, which was like riding on chewing gum. My funniest moment at MM was my first lap on the powerbar climb. When I was at the bottom, I was pretty much the only ride on the climb. At that point, my friend Lisa saw me from where we were camped half way up and started shouting 'come on Kirstie' etc. Before I knew what was happening, the whole of the powerbar spectators were cheering me on. I was laughing too much to ride at anything like race pace!