Hey! Thanks for your question! I'm going to go lightly in depth in my answer as 3000 years is a lot to cover, so I'm going to give a little info on each of the artistic aspects you mentioned. (also I'm writing this on mobile so apologies for any paragraph mistakes).

First - hieroglyphs. Hieroglyphs evolved massively over Egypt's history, so much so that we have several distinct languages and scripts. The 'traditional' style of hieroglyphs which everyone thinks of is known as Middle Egyptian, the pictorial language you find in the Middle Kingdom (2055 BC - 1650 BC), and which survives as a written language until around 4th C AD. This is mainly due to the fact that the Middle Kingdom was a boom of culture and literature, and judging by later examples of language, hieroglyphic writing almost seemed to evolve as if it were trying to 'get back' to that time.

Before Middle Egyptian, we also have Old Egyptian, the language of the Old Kingdom (2686 BC - 2181 BC). I personally don't know a lot about this however it was distinctly different from Middle Egyptian, with different grammar and conventions. It was also mostly spoken rather than written. After Middle Egyptian, we have Late Egyptian (1069 BC - 700 BC), which began around the Amarna Period (New Kingdom) and the Third Intermediate Period, and has somewhat similar grammatical conventions to demotic.

[Note - there is also Ptolemaic hieroglyphs, which are a later version of Egyptian which I don't want to go into as I've never studied them, so it'd be wrong of me to give false info, and I'm trying to cover as much as I can from your question]

The three languages I've just mentioned can be written two ways, with hieroglyphs or hieratic. Hieroglyphs are of course the traditional signs, while hieratic is a more abbreviated 'common' script. Its used for administrative documents and letters, but also literature and is seen in the Book of the Dead. It was easier and quicker to write, and made language more accessible.

In later periods, we have demotic and coptic. These appear in the Late/Graeco-Roman and Coptic Periods respectively, but survive until much later. Coptic survived until around the 16th C AD, while demotic until the 5th C AD. Both scripts involve signs which are similar to Greek, rather than pictorial hieroglyphs. However it is possible to trace the origin of some words and signs all the way through from Middle Egyptian, to Late, then to Demotic and Coptic. As a result, while it may seem like there's one type of hieroglyphs, there is a huge variety in style and script between each language, particularly grammatically and artistically. Each scribe had their own handwriting, and as a result signs are sometimes written differently depending on the text.

(I'm going to reply to this comment with further answers on artistic style).

If you want to know more about hieroglyphs I highly recommend checking out the work of Mark Collier and Bill Manley. Also the work of Mark Smith is excellent, and in 'Searching for Osiris' he tracks representations of Osiris through Egyptian history, which may give you more info on art and language, albeit in quite a specific subject.