I see that you like the Rustic look. . .and understand why. . but be careful, what's "in today" may not be "in" for the long haul. You could always still do hardiplank, which you can paint later on down the road and offers easy upkeep. That said, by adding a rustic door and/or rustic shutters (or no shutters at all), rustic porch with old barn wood. . you can really make something fresh and new, look old and rustic. Use the "details" to get the rustic look you want and the character you desire. Just a thought! Good luck!

I wouldn't consider hardieplank to be rustic at all. Why not board and batten or shingles?

Yep, board and batten is a classic and timeless "rustic". Shingles maybe not so "rustic", but very textural and can be stained or left to weather naturally, which does become rustic over time. So much depends on the architectural design of your house. Why don't you post a perspective or even an elevation so that suggestions might be more applicable?