From my POV.
I started with an EA, and It was pretty awesome, channel is easy to get, you have the highest range, immunes, dashes, stealth, cc on low cd without chi req. Etc.... With the cost of being squishy.
Easy to play doesn't make it easy to master.
And very easy to get points on NW with it aswell
If you are starting off, do not worry to much about the aps and the def gear at start, unless youre planning to 1o1 alot, then rush def aswell, Aps is mostly for mass.
MG however felt very clumsy, and slow, since getting channel was way harder. But getting it down feels rewarding. And the cast times are longer than EA's. Unlike archers, you must be aware of what each skill does, you cant just spam like crazy. I won't lie using genie spark and one shotting peeps isn't awesome, but that won't work on experienced players easily, which means you cant rely on it. You also need 97-99% chann to reach max potential.
You also have a shorter range, which can be a struggle, you will also be required to go in close with Ice prisons on mass, which can make you vulnerable. MG is just mostly practice and practice and practice.