Gpmo welcome to the madness.
Have not loaded in yrs but I first used a hand press to load like twenty .223 rnds.
After every one of them went boom I was hooked.
You mention powder and the diffs. Other than burn rates and shapes you'll find the with all other factors being the same a change of powder at same weight may yield a more accurate load. Some powders shoot 'soft' yet develop great velocities.
You cannot go wrong with a Dillon anything. And their customer service is second to none. I wouldn't worry so much about powder sensor but with that press you are getting you can untilize the quick change heads. Invest in those and the stands for them.
This way you load a set amount of one, swap heads, drop cases and maybe different primers and off you go again.
However once you get good and comfortable with the process you will most likely want to get a small single stage press for your target bolt guns. There's just something a lot more satisfying about slowly hand trimming and sizing a case and then priming it again by hand with just 'the feel' from having done it before, then you load your powder and seat the round making sure it's set in the case and turned 'just right', then slowly you pull the lever down and create another carbon copy of the last one you made. Then after about twenty to thirty minutes you can make another one.
Keep accurate detailed records of everything no matter how small or insignificant it may seem. If you start having problems or success you'll want to be able to go back step by step and recreate or rectify things. Be careful and enjoy your newfound addiction. You'll soon be reading Speer loading manuals and dreaming of new loads you can make.
The beauty of reloading is that there are so many more loads and weights of bullets you can use in each caliber.