Maybe the best way to start would be to define what it is that you don't like about the Big Agnes.
Is it not providing enough wind/rain/cold resistance? If that's what you want to improve, then you will probably have to go a bit heavier tent. Less mesh. Stronger pole configuration...
Is too heavy? If so, then you are (realistically) going to have to give up a significant amount of wind, rain, snow, cold, or bug protection to save some ounces. You have to decide how much you are willing to sacrifice versus how much weight you can save...
If it's too small, then, you would have to look at bigger, slightly heavier tents.
Personally, I probably wouldn't want LESS weather protection than the Big Agnes, but I hike in New England where rain or bugs or cold or wind could be on the menu on ANY given day.