Okay, let’s do it without statistics if you don’t like them 
.
You say “aiin” is “utis” and its variations? That piqued my interest. I therefore counted the endings you appear to be treating as variants, purely as letter sequences and irrespective of grammatical context.
Percentage of all words/tokens in the Latin corpus that end with this sequence of letters.
-itis 354 0.277%
-atis 314 0.246%
-etis 317 0.248%
-ati 196 0.153%
-iti 66 0.052%
-otis 48 0.038%
-uti 39 0.031%
-oti 29 0.023%
-utis 23 0.018%
-eti 15 0.012%
so: In my Latin biblical corpus they occur in 1.10% of all word tokens combined.
As an independent check, I ran exactly the same count on the Latin ITTB corpus (334,471 alphabetic word tokens, largely Thomas Aquinas). There they account for only 0.643%.
Total “aiin” sequence in the VMS: approx. 3,948 occurrences 10.2 % (!!!) of the tokens
Show me a reasonably sized continuous Latin text in which these endings even reach 3% of all word tokens.
. You say “aiin” is “utis” and its variations? That piqued my interest. I therefore counted the endings you appear to be treating as variants, purely as letter sequences and irrespective of grammatical context.
Percentage of all words/tokens in the Latin corpus that end with this sequence of letters.
-itis 354 0.277%
-atis 314 0.246%
-etis 317 0.248%
-ati 196 0.153%
-iti 66 0.052%
-otis 48 0.038%
-uti 39 0.031%
-oti 29 0.023%
-utis 23 0.018%
-eti 15 0.012%
so: In my Latin biblical corpus they occur in 1.10% of all word tokens combined.
As an independent check, I ran exactly the same count on the Latin ITTB corpus (334,471 alphabetic word tokens, largely Thomas Aquinas). There they account for only 0.643%.
Total “aiin” sequence in the VMS: approx. 3,948 occurrences 10.2 % (!!!) of the tokens
Show me a reasonably sized continuous Latin text in which these endings even reach 3% of all word tokens.