I think you could do this with plain linux bash scripts. 60,000 words isn't really that many, in this age of multi-GHz CPUs. The following Linux command seemed instaneous on an older rack-mounted RHEL server:
4 % wc -l /usr/share/dict/words
That's a lot more than 60,000 words. Between
uniq you'll have most or all of what you want to do.
My advice is to develop text manipulation commands as pipelines, using
more as the final stage:
1 % cat filename1 filename2 | tr -cs "[:alpha:]" "\n" | more # there's your words
2 % cat filename1 filename2 | tr -cs "[:alpha:]" "\n" | sort | uniq | more # unique words
3 % cat filename1 filename2 | tr -cs "[:alpha:]" "\n" | sort | uniq -c | sort +1 -1 | more
You just use terminal editing features to add another stage to the end of the pipeline until you get what you want. Then, cut-n-paste the final pipeline into a text file, make that into a shell script, and you've got a software tool.