In his Neo-Quenya New Testament (NQNT), Helge Fauskanger used the neologisms ascarë and ascárima for “easily done” and “easy [to do]”, both combinations of the prefix as(a)- “easy” and forms of the verb car- “do”. Tolkien himself had ancárima “easy, very doable” in Late Notes on Verb Structure (LVS) from 1969 (PE22/155) using the intensive prefix an-. However, I think Fauskanger’s neologisms are still useful, with ascárima emphasizing something requiring little effort to accomplish, while ancárima emphasizes the likelihood of success.