Once you get used to a convection oven, you will like it. You do need to purchase one that vents out the front so you don't have to put venting out thru the side of the trailer. You will have to look at size more so than a brand to get what fits in the space you have.
The grill mounted on bumper. I wouldn't want that as they do get hot. I worked in insurance and I can't tell you how many claims were paid because people had gas grills next to their houses (sitting on the deck) and it melted, scorched or burned the siding on their homes. Wouldn't want to clean the grease off either and what about when you have the fire flare ups while cooking?