Unless your lifestyle allows you to get into a four-year college program, most available Japanese classes will dump you back into the world at the High Beginner level (JLPT level 4 would be easy, level 3 is quite possible with some study, but you’re in desperate need of real conversation practice, and functional literacy is waaaaaay out there in the distance).
One real frustration is the lack of good reading material. Things intended for Japanese kids will have the furigana you need, but assume a much larger working vocabulary, as well as cultural context that may turn a simple sentence into a half-hour Google search.
Late last year, Ask released a set of graded readers in four clearly-defined levels. I stumbled across them a few weeks before my trip to Japan, and picked up the level 3 edition. It was quite readable.