This isn't the best way to "enjoy the scenery" but to block heat (that mostly comes in through the many large windows on your Class A), you may need to completely block windows during certain times of day on the sunny side of the rig. Reflecting back the heat/sun helps, and some folks have fashioned custom-cut pieces of cardboard (or similar) lined with aluminum foil on the outer-facing side. If you have skylight openings, those can let in quite a bit of heat that builds up too. Run A/C early enough to keep things cool, rather than trying to "catch up" later once the inside gets hot.
The sun shades you mentioned may block brightness and glare a bit, but I doubt that they will substantially reduce the greenhouse-effect interior heat buildup on hot days.