Congratulations and welcome to the forum.
The battery on my 1999 Plus 8 is eight years old now and still spins the engine over effortlessly, never been on a battery charger but I do have a battery Isolator switch which I throw when leaving her without a run for over a week.
The newer models have a lot more alarm/electronic gizmoes and a few people leave them plumbed into an intelligent trickle charger, having worked in electronics my whole life I am not a fan of this practise.
I'm sure you have answered your second question.
Enjoy your miles and don't lock it away in winter if there is no salt around.
some of my very best runs have been in winter in light snow on Dartmoor when only the farmers are about.
