Yeah, quite a lot of recently released Light Novels indeed do have long titles.
Besides the already named ones, Yahari Ore no Seishun Love Come wa Machigatteiru. could also be an example, hehe.
I personally think they can lure fans into buying them and make quite a success if the long title is well picked and the cover looks great, but still, the top Light Novels will already have short titles.
Long, funny/interesting titles are made to attract people to a certain limit, but that limit is already so high that actually having a long title is safer than a short title nowadays. :D