Is an SLX M7000 crankset compatible with the rest of my drivetrain?
I'm not sure if there would be any problems mixing SRAM and Shimano per se. The SLX crank is a higher end component than the X5, so you would be buying more than you need, and you get problems mixing 9 and 11 speed components.


The 11 speed SLX crank uses a narrower chain than 9 speed. The 11 speed chainrings are slightly closer together which may give you shifting problems and chain rub as your front derailleur is designed for 9 speed chainring spacing.
By choosing a 24/32 crankset instead of 22/36 you'll be loosing high and low ratios. The smaller chainring gap on the SLX is made up for by a wider spread of sprocket sizes available in 11 speed cassettes.


Upgrading one component several steps - even something major like the crankset - does not make a significant difference to the bike overall, and here you'd be introducing other problems. Better to play it safe and get a SRAM crank. I think all SRAM X-5 through X-9 cranks are now nominally 10 speed but each line includes 9 speed rear derailleurs so they should work fine for you.