I'll try to break this down in order to keep thoughts organized. First, good for you on a lifestyle change. I was about 34 when I realized I was turning into a fatty. I turned it around and am in better shape at 41 than I was in my late 20s.
Diet suggestions: I don't know what you like to eat, but this is what I do for breakfast. If I have to eat on the go, I take granola and put a cup of greek yogurt on it along with the frozen mixed berries from Costco. Frozen blueberries are good too, and plain or vanilla yogurt also work. Just watch the label on your yogurt because some of them are very high in sugars/carbs. The greek yogurt is much higher in protein and lower in carbs.
If you don't like that, maybe look at a bagel sandwich such as a whole wheat bagel, a fried egg, and a slice of white cheese or a sprinkle of parmesan cheese on there. These are easy, and you can throw on tomato, avacado, tobasco, a slice of ham, etc. to add some variety. These are super easy to make up quick and eat on the go.
Lately, my wife and I have been doing lots of smoothies for breakfast. We buy protein powder from Costco and do a scoop or two of protein powder, a banana, half cup of greek yogurt, a splash of milk, ground flax, and then whatever for flavoring. Frozen berries work well, as does peanut butter.
I try to avoid eating lunch out like the plague. It's unhealthy, and you save a buttload of money by doing so. I usually take some snacks like nuts or trail mix, several pieces of fruit, carrots, a cliff bar or two, and a sandwhich or some type of leftover. I figure by taking my lunch every day I save enough in six months to pay for my out of state hunting tags.
Dinners we always have a lean meat serving (i.e. chicken, elk, deer) and grill as much as possible. We always either have a cooked vegetable or salad, and a side dish like brown rice, quinoa, pasta, etc. Try and avoid simple carbs as much as you can by avoiding white breads and the like. We eat a ton of whole wheat/whole grain foods, but always try to limit each meal to one kind of starch dish (i.e. avoid both bread and potatoes, choose one).
On to your shoulder. I would avoid taking the bar any lower than a 90 degree bend in your elbows on your bench if I were you. It's your body and your choice. However, having rehabbed a shoulder injury I can tell you that two of the hardest lifts on your shoulders are lateral shoulder raises and bench presses off of your sternum. I usually try to lift one day a week, and focus on dumb bell lifts as much as I can. Especially on benches, they give all of your stabilizer muscles a much greater workout.
Core exercises you can do planks, do some Yoga (which will do wonders for your lower back and hamstring flexibility), functional exercises like frontal squats, deadlifts.
I like to get as much variety in my workouts as I can. I try to do one day a week of plyometrics, sometimes two. You can do these workouts anywhere, and in 45 minutes or less you can absolutely smoke yourself. I try to ride my mountain bike one day a week, run a couple, and lift one day. I do lots of functional body weight exercises like lateral jumps, burpees, pullups, pushups, walking lunges etc. My times on trail races have improved the less I run and the more I mix in other types of training. Injuries are non-existent, and I can hunt longer and harder than I ever have.
Good luck!