The JL is a whole different animal. The issues that you had with your JK and 35's won't be the same with the JL. First the harsher ride has to do with the type of tire more than the size. You get a 33" mud terrain tire and it's gonna make noise and ride as harsh a 35" or 37" mud terrain. So pick an AT tire or an aggressive tire that's known to be smooth on the road. Second the larger tires on the JK and mpg's has to do with the gearing and the engine of the JK. You'll experience a lot less of that with the JL. The Rubi comes with 33's and most people who jump to the 35's can't tell much difference. The speedo and mpg's will be off just a bit but nothing that will break the bank or can't be fixed by reprogramming. I had a JK with 35's and a 3" lift and it was a beating on the highway until I re-geared and re-programmed but the new JL you won't have as much of an issue.-been down that 35 road before with a previous JKU and dealt with the shortcomings of 35's (harsher ride, decreased fuel economy, etc) and don't want to be in that same boat again so to speak.
Last but not least... I totally get the money thing. If you're set on the 33's and don't want to spend the money on 35's just yet I would go ahead and buy your lift and just hold off on install until you're ready to upgrade tires.