It would be extremely helpful if you tell us how much you want to spend on a tent, and how much for the panniers. Otherwise, I could show you a tent that weighs a pound but will cost you $1,200! But maybe you can afford that, or maybe not, you need to let us know what you budgeted for each thing.
As far as leaving the panniers on the bike, mine easily clips on and off so I take them and put them under the vestibule of my tent, even though mine are extremely waterproof, I don't want critters trying to get access into my panniers either. You rode the bike with food in those panniers, even though you removed the food, the smell is still inside the panniers, they could tear open the bag to gain access for what they hope will be a free meal.
I think Ortlieb makes really good panniers, but I opted for Axiom Monsoon Oceanweave 45 liter (23 liter each) bags, I think they are about the same quality as the Ortliebs but at the time I got these they were $125 cheaper for a pair than the Ortliebs were, I think I paid $145 on sale, and I've had mine now for 3 years and have no wear on them. Axiom raised their prices but I haven't compared them to Orlieb today. I know the Axiom bags are very waterproof, because I had to ride in a downpouring rain, this was hard and a lot of rain, so much rain that a river I had to cross the road was closed because it had breached the bridge. Nothing inside those panniers even got remotely damp not alone wet, and at the time that happened I hadn't bought the optional rainflies. The reason I got the rainflies was due to the bags are black, I wanted something that would stand out, so these are a neon yellow color, plus they would protect the bag from dirt and wear. Some bags you have to be careful about considering because they could weigh 4 pounds like Banjo Brothers and Thule bags, whereas my Axioms are half that weight. There are some other brands to consider as well, like Arkel Orca 45 but probably the most expensive one on the market. If cost is an issue, and you want something a bit less expensive then you can't do better for the price than the Burley Pannier set found at REI for just $90 for the pair, but these are more for the front since they are only 11 liters each; unless you use 4 and put 2 on the front and 2 on the rear. Another budget pannier for the rear is the Crosso Dry Pannier at around $80 for the pair, with a huge 30 liter each capacity, and they are waterproof! Made in Poland, not China as some would assume for the price.
Tent wise. The best is maybe the Hilleberg Enan solo tent, it weighs 2 pounds 10 ounces but cost $680, but for the cost you get very long life. You can get a lighter tent for less, the Nemo Hornet Elite Osmo is only 1 pound 10 ounces, and it cost around $500. Now if you're thinking someone has to be nuts to spend that kind of money for tent, then take a look at the REI Co-op Passage 1, this only weighs 4 pounds 10 ounces but cost under $100. That's what you pay for, the more you pay the lighter it gets, like anything in this camping biking world. As with panniers, there are other great tents as well, I only mentioned a few. By the way, with tents you have to spray the tent with waterproofing spray every season, and reseal the seams, I would do it as soon as you get the tent before your first outing, just to be extra safe.
If you're going to be in bear country, you may want to hang your panniers, along with food about 100 yards from your tent, instead of keeping them inside the tent area. Yes, that is correct, 100 yards! and 15 to 20 feet up. Also, you cook all your food 100 yards from the tent. I've seen diagrams of a triangle, where you cook your food is 100 yards from not only your tent but also from where you will store the food. Also, you put your tent upwind from the cooking area and food storage. Seems excessive but bears can be excessive. Some people suggest only 200 feet away, fine, you decide how nervous you want to be near a bear, but most people recommend the 100 yard thing. Of course, if you're going to be in bear country you may want to take bear spray.
