No, I need to go back to 3 rings on the front.
Have a look at a gear chart and you will see that most gears are duplicated if not triplicated, which is one of the points behind 2x*
Have you ever done a 24 hour solo or a 7 day mountain bike stage race?
If your racing you need to get stronger. There are reasons why 2x* makes sense.
If you want to go back to 3x* do so, but be aware that if you pick the right chainrings and cassette there is very little benefit to be gained. and you do gain a few problems.
As for climb size, Le Chable to Col de Gentiannes in the Val de Bagnes on a 2×9, in prep for the Grand Raid Cristalp. Is that a big enough climb?
Climb hardness has nothing to do with size, the south downs vs the Cairngorms, they are different nothing more.