School left me with the impression that hieroglyphs were primitive constructs - purely logographic and ideographic. It was a shock to later learn that they are also alphabetic and phonetic.

The opportunities for creative expression are amazing in such a system

Yes, the system is reminiscent of written Japanese in that way in that a word is sometimes spelled out phonetically, sometimes with an ideograph, and sometimes both for good measure if one or the other isn't viewed as clear enough.

No wonder the scribes were so highly regarded

Very few, if any, real world writing systems are purely ideographic.