My blades haven’t rusted, that’s not the problem. And by the way, Matrix blades are stainless with an aluminum chassis, so rust shouldn’t really be an issue anyway.
Stainless rustproof isn't completely rust proof. I had some Matrix blades (440 alloy - possibly 440C) in a place that flooded. It destroyed them.
Even aluminum can be destroyed by exposure to salt water, or dirty water. I've had that problem with kayaks, roof rack bolts, and the bolts that held on truck caps. Some times the only answer I know of is to cut off the head, and/or drill out the bolt, use a tap and die kit, etc.
But those are pretty extreme conditions. If you dry out your stainless steel blades after use, it probably won't be a problem. Unless you skate on salt water, or natural ponds.
Unfortunately, most of the MK and JW blades that you are considering are not stainless steel. They should get more care. And, at least in my experience, they need to be sharpened more often (and will therefore have a shorter lifetime - though not, I would hope, as short as your Matrix blades are having) - as though some corrosion actually occurs while skating. But maybe there is a way to prevent that.
Anyway, your coach might be able to tell you how typical your issues with breakage are at your level.
Maybe it is worth doing the repairs others have mentioned on your Matrix blades - i.e., putting the screws back in, with a thread lock compound. That doesn't seem too much work. Won't fix the broken blades, but will deal with the most obvious parts. Also, if you glue in some padding between the runner and the slot it fits into, I think that will fix the "clicking". Mine fell out (this was on a prior generation of Matrix blades, that was designed to have replaceable and interchangeable runners, which I still use), but I didn't want to use glue.
Incidentally, modern Matrix RSX blades are also designed to have replaceable runners - though different styles aren't interchangeable, and the toe picks are fixed. (But RSX blades are remarkably expensive.)
I assume, based on your skills, that you skate
a lot. Depending a lot on exactly how they are sharpened, blades should last through about 30 sharpenings. Even if you sharpen every 2 weeks, they would last about 60 weeks. If yours are only lasting 1/2 year, that is IMO unacceptable. But maybe that would be better, if you do those repairs.
I know it is impolite to ask your weight. But would you be willing to give it? I doubt you are all that heavy, considering the skills you are doing, but if you are unusually heavy - though remember that high level blades are also used by high level men, doing quad axels - that might explain breakage.