When I was 1800 I still lost heavily when playing Open Sicilian. I won against the Sicilian of course, but usually in very irrational and tactical games. My results, however, were unstable even at 2200 when I still played 1. e4. If you think that you do not want to handle very sharp positions, especially in the Open Sicilian, and you generally play positionally, I think 1. d4 would be good to at least start studying now. The last 1. e4 game I played was a Najdorf 6. Bg5 against an IM, and I spent more than one hour on the first 13 moves and nearly lost on time. Luckily my opponent was confused about the position too and spent most of the time on the opening, and the only reason I drew was because the game terminated in time trouble for both of us and somehow it became a drawn endgame.

I find 1. d4 easier to play, since 1. e4 was more difficult for me when I played Open Sicilian. I lost many sharp positions against the Najdorf, Taimanov, Kan, Dragon, and Sveshnikov against lower rated players, but somehow my results have improved with White when I switched to 1. d4.