You're going to get lots of opinions in a forum like this, but based on your criteria, I think you would be quite happy with 18m Matrixx you mentioned. They are really forgiving kites, kind of gentle giants - which sounds like it might be great if you're a big guy and want to get out in light winds - which is often the best time to learn, because winds are less gusty typically when they are light. The Matrixx is lightweight and packs down small, and has all the lift you would want or need as a beginner.
As others have said though, I would start with something like a Peak 4 or Apex. You will be crashing quite a bit while you are learning, so you don't want to do that to a closed cell kite like a Soul or Matrixx - which you will be more likely to burst and damage if you crash.
I don't think you would go wrong with either a Peak 4 or an Apex. If choosing an Apex, I would recommend an Apex V or HQ4 Apex. I've ridden both the Peak 4 and the Apex - the Peak 4 will produce more power per size, but has a heavier feel in the bar. Neither of the kites are made for jumping, but both will jump a bit with the right timing and winds. I found the Apex to be a little easier to jump, but it may be because I am more used to the kite.
I would also say that if you can find someone who has one or get a demo: the Little Cloud Pelican is a fantastic kite: super lightweight, very user friendly (as good or better than the Matrixx), great lift and efficiency. The largest size is 13m however, and as before - I wouldn't make this your 1st kite, as I wouldn't want to be crashing it a lot. Find another cheaper used kite to beat up first
If you decide to go with that Matrixx, here is a something I recently did to makes kiting on land a little safer, and you will be less likely to blow up your kite on a crash: you can roll up the inlet socks and make it more like an open cell kite when you are operating on land. I've found it works really well: