Congrats on your GA, I use mine atleast a couple times a week. About your Temps, Use Lump it's way hotter. You also might try lineing the inside with HD foil. Makes cleaning it alot easier. I also cut a spare piece of expanded metal to lay on top the charcoal grate when useing the Lump.
UDS, Jumbo Joe 2013, 26" Weber, SS Blue Performer, WGA Charcoal, Q100 & Wife Model#1962