I had an idea today for a new candle type, not sure if this exists anywhere but I've never seen it.
The idea is quite simple, to use a renko/range candle or box, but add a time element to it whereby if trade doesn't break out of the range, the candle continues to paint a horizontal bar until range does break out. Therefore you will have long flat horizontal boxes in range trade, and narrow bars as the bars do break out.
This way you can see long periods of consolidation, unlike a normal renko, and these act as natural support levels for the breakout. It also makes identifying a break easier.