GrillGrates(TM) amplify heat, prevent flareups, make flipping foods easier, keep small foods from committing suicide, kill hotspots, are easier to clean, flip over to make a fine griddle, and can be easily removed and moved from one grill to another. You can even throw wood chips, pellets, or sawdust between the rails and deliver a quick burst of smoke to whatever is above. Every gas grill needs them.
Hey Charlie – I’d leave that grate wide open if you want maximum heat. If the grates are only over the burn pot, then you can do sort of a two zone cook (indirect vs direct heat) by putting a thicker steak, chop, or piece of chicken on the ‘non direct’ side to get up to a temp that’s 15 or 20 degrees lower than your target. Then, finish off over the burn pot area. Just one idea.
Camp Chef has already been mentioned several times on this list. It's a venerable company that makes up in quality what it lacks in the name recognition of a Traeger or Weber. Their Deluxe Pellet Grill is built to reach and hold ideal temperatures for smoking. An internal system syncs pellet delivery to temperature instead of simply feeding in fuel when it begins to run out. This ensures a clean, consistent cooking experience. A removable ash can makes clean-up a snap as well.