I like 8bit PICs but here’s some advice:

• You want to use assembly. Really, don’t mess with whatever crazy (non-ANSI) c compiler these clowns are pushing. Assembly (particularly on these chips) is not hard.
• MPLAB X is horrible, it takes all the things I love about PICs and makes it complicated.*
• Don’t mess with the PICkit3 it only works with MPLAB X. You want the PICkit2, it works with pk2cmd. If you really need those debugging features then it’s time to move on to something with an ARM core (Serial Wire Debug gdb and all that)
• If you need to do math use a lookup table (array). If your math is complicated then do it in C and use something with an 32 bit ARM core (read: not a PIC); these things don’t have FPUs. Really, most of them multiply by adding in a loop, an FPU is like a pocket calculator for your CPU.
• Use the simplest chip you need to do the job, start out with something with with a modest number of peripherals lest you be overwhelmed.
• Really, learn assembler your going to get stuck anyway and have to write some assembly anyway… and it’ll make you feel smart!

* What they’re really up to here is to immerse you in their marketing madness. Hey Microchip, if ya want me to use your high end chips than you need to contribute to gcc or clang or both, if it’s not an open source ANSI compiler I won’t use it, I am not going to learn your crazy dialect of C or pay you for the privilege of writing code that will create demand for your chip!