The noun reflect has a long history. Citations from Oxford English Dictionary go back to 1594 and the most recent quote is from 1996:
B. Siegel World of Autistic Child (1998) ii. xii. 298
Lack of enthusiasm for a new job or any new setting is common in autistic people, and may mostly be a reflect of their dislike of things that are unfamiliar.
The meaning is the same as reflection, sense 1 and 3, OED, which I assume you're familiar with and can get from this example and the one you cite.
English won't break if you do drop the -ion from nouns. What to wonder is will anyone else follow you in doing so. Language is a creative medium, like paint or clay. English survived all of Shakespeare's and others' coinings and "violations".
Invent was used as a noun in the early 17th century but it is not anymore.