Archiving your file in the Genealogies section of FamilySearch is a good option, I think: your work will be freely searchable and available, with no ads or paywalls, but nobody will be able to change anything. (Not even you, except by deleting the file and uploading a new one.)
The only drawback I can see is the general confusion that's prevalent about what FamilySearch really is or what it does. There are people out there who apparently honestly believe that Historical Records on FS is a different entity than the Family Tree on FS; they create different logins for the two, and are surprised when they use the wrong login and can't see themselves in Tree. The other extreme also occurs: many people discount everything FamilySearch -- even images of historical records -- because of errors they've encountered on the Tree or in indexes. There is also widespread ignorance of the collaborative nature of FS's tree, and the separateness of the Genealogies section, and lots of misinformation about how all this relates to the LDS church or to for-profit organizations like Ancestry.
It has been a few years since I used FS's upload, so I don't know if this still applies, but you should make sure _not_ to procede to the "import into Tree" part of the upload process. It's ancient code, badly broken and badly presented; I hope they've gotten rid of it, but things like this move Verrry Slowwwly at FS. (As I recall, the process made it much too easy to accidentally create duplicate profiles and/or override years of research with a single unintentional click; it didn't show everything I needed to make sane judgements, and was misleading about what my actions would actually do.)