Has anyone here read any of the books by Tovey e.g. Essays in Musical Analysis? Are any of them worth seeking out?
I bought his “A companion to Beethoven’s pianoforte sonatas”, they have good insights but the language is very technically dense. Much of it goes over my head 
I haven’t read him (well maybe an extract or two) but I’d definitely be interested in it.
Also what do you mean by technically dense?
it’s full of harmonic/structural analyses or does he use a lot of big words?
If the former, you should probably follow along with the score (or do your own analysis which is generally my preference).
In any case, I think you should give him another try.
I’ve read him but I don’t think his writing is especially apropos to interpreting the pieces he writes about. He’s of the old fashioned perspective (shared by Charles Rosen and others) that the primary task of the player is to show the abstract “structure” of the piece over “expression” or subjective ideas.