Play with an online bicycle gear calculator (this is my favorite). Click 'compare two setups', and put your current bike into one (or probably your current bike as a double with no granny, since that's how you use it) and play around with gearing on a second bike until you get a range/spread you like. I bet you could do very well on a 1x, if you are currently not using your granny at all. They make very wide cassettes now, up to SRAM Eagle 10-50 (but that takes a special derailleur). It should not be hard to slap on a 10 or 11-speed 11-40.