Engagement Rings?

Is it bad that I don't want a big expensive ring? Or hell, even a real diamond? I love the look of other stones especially on a dainty ring. Of course I want a more precious metal because I want it to last and not turn my finger green, but I just want to live the rest of my life with my SO, not have him spend his life savings on a ring for me. If he proposes, then I'll know that he loves me, no matter what the price of the ring is. He plans to propose soon but he fears that I'll turn him down if the ring isn't obsurdly expensive (what?) and if he doesn't propose to me in some extravagant way. Like. If you hand me a claw machine ring and say "will you marry me," I'll bawl my eyes out.