Yes, most Christians believe in heaven. Your assertions about heaven are really problematic. Even before Christianity, many Jews formed a concept of heaven as they borrowed the idea of immortal souls from Greek philosophy & the idea of good people earning an afterlife in paradise from Zoroastrianism. Hence frequent references to heaven in the Bible, esp. in the later books of the Hebrew Scriptures & of course throughout the Christian scriptures, too.

Theologically literate Christians reject the "God has a plan for me" concept. Many years ago, an Episcopal priest reviewing a speech I was going to deliver in church corrected me when I lazily asserted God has a plan for all of us (a leftover idea from my earlier experiences in evangelical churches). She patiently explained why the idea violates the concept of free will, which is central to orthodox Christian theology (so, not just Episcopalians, but pretty much every denomination except evangelicals). I modified my speech accordingly.