I don't like the majority of modern helmets. There is just far too much going on with them, and they convey very little. I prefer a much more minimalist designs, the best of which is:

The design is simple, but it conveys every a driver could want. The yellow is striking and goes with the stripes to clearly show Senna's nationality, something which was very important to him.

Ayrton Senna: WDC 1988,
1989, 1990, 1991
McLaren: WCC 1974, 1984, 1985, 1988, 1989, 1990, 1991, 1998,
1999, 2007McLaren: WDC 1974, 1976, 1984, 1985, 1986, 1988, 1989, 1990, 1991, 1998, 1999, 2008