(1) When do you plan to go? Note that because of the unusually high snowpack and cold wet spring, the snowmelt is almost a month later than normal this year all over the western US, except for AZ and NM, which are suffering extreme drought (if it isn't one thing, it's another!). While all areas from southern Colorado northward have above-normal snow, it seems to be worse as you go north. If you're planning to go before August, you will probably have major problems with both lingering snow and high water at stream crossings.
(2) There are many mountain ranges all over the western US which are just as scenic and far less crowded than those in national parks, including the Tetons. Most of them are part of good-sized national forest wilderness areas. The one problem for all of these areas, this year, is the delayed snow melt.
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey