I only ever go on holiday with hand-luggage; it's a weird phobia about being separated from my things.
Remember, you only have to get past the check-in. So, first tip, pack some of those cotton bags that come free with magazines, and things. Put them at the top of your case and, once you've "passed" check-in, decant into one of them.
I would wear the heaviest shoes and clothes. So, if you're going to bring a coat, wear it. And I do things like wrap a cardigan around my waist!
I've only been to warm climes, and have no idea about Marrakech at this time of year, but this, off the top of my head, is what I pack:
2 pairs of shoes, with the option of buying a cheap pair of plimsolls that will be destroyed on the beach on holiday/in the airport. "Going out" shoes = ballet flats. Walking shoes = converse. (I'm clearly not as fit as you).
3 x T-shirts, in black and white, 2 of which are long-sleeved (I burn); white, long, Indian-cotton shirt; 2 x dresses (at least one of which can be worn with T-shirt underneath); 1x skirt, 2 x cardigans; 1 x Indian sarong-thing, large, swimsuit, tights, socks.
I make sure everything "goes", indeed, most of it ends up being black!
And then I add more, depending on space. I tend to pack books, too, and children's stuff. You can pack quite a lot in, really.
I roll everything, and do the thing of sticking socks in shoes!
I'm strongly inclined not to post this, because I'm a little worried I sound a bit bonkers!