Esperanto books difficulty rating

I have started learning Esperanto and have found some books I will use to read to help learning here: http://i-espero.info/files/elibroj/

Some of them sound pretty heavy (e.g. new testament) so I want to put them in an order of difficulty before I read them

I reckon length, and number of unique words will be the best way to do this (length of sentence might be good, but the implementation of that will be tricky)

here’s the code: https://github.com/fi1ingcabinet/esperanto_book_review

here’s a table of some of the result (full result in the repo):

(I multiplied number of words by number of unique words to get a level of difficulty I will broadly follow to read them)

Author	Title	num words	num unique words	num pages	num words*num unique words
bunin, ivan	facila spiro.pdf	1600	687	3	1099200
loira, augusto j.	cent dek tri humorajxoj copy.pdf	5024	655	49	3290720
feldbaum, sigvard	juda sagxo.pdf	2880	1175	51	3384000
galeski, viktor	kalejdoskopo.pdf	3191	1363	65	4349333
luin, franko	spuroj de miaj pasxoj.pdf	3269	1341	52	4383729
jokai, mor	la du salikoj de nagyenyed.pdf	6788	2750	33	18667000
gogol, nikolaj	skribajxoj de frenezulo.pdf	8381	2446	48	20499926
szilagyi, ferenc	tra mia prismo.pdf	7040	2935	83	20662400
z., hasse	jakobo k.c..pdf	12764	3227	57	41189428
codjo, jean	dialogo inter surduloj.pdf	13079	3207	58	41944353
schwerin, p.e.	gaja leganto per esperanto.pdf	11607	4565	67	52985955
lagerkvist	mariamne.pdf	15963	3324	66	53061012
schwartz, raymond	la stranga butiko.pdf	11775	4567	130	53776425
dickens, charles	la batalo de l’vivo.pdf	29975	5510	106	165162250
sierosevski, vaclav	la fundo de l’mizero.pdf	28875	5732	111	165511500
vallienne, henri	kastelo de prelongo.pdf	153271	20428	712	3131019988
kardec, allan	la libro de la spiritoj.pdf	242325	15130	475	3666377250
wennergren, bertilo	plena manlibro de esperanta gramatiko.pdf	257667	24767	711	6381638589

Also here is some resources: gutenberg.org/browse/languages/eo