As you say, getting less easy and less certain
No, no, and no...however, I will say I originally thought of using ZAX...but decided to change it :c)
I will also say that after creating this, I haven't actually gone through and checked how easy it would be to solve...so, really all I can say again is notice that there are not many 0s in that grid...
Also, I'll let you know that words J, U, Y, and Z are not super common (along with the X and Q that has already been solved)...but the rest are pretty normal