Tips to playing arty *snip*
Agree with everything especially #1 and 2, though I would like to amplify #4. If you are skilled at TD mode (aka not sniper mode), and you know the scout is coming (ample warning to turn/get around a corner), I go for the kill so that I can put more rounds out later once I kill the scout. I also play American arty so I have a decent turn rate. If I got a nice juicy target (m103), and the scout is in close before I spot it (ie no chance of turning in time), I would fire on the m103, then ram the scout. Ramming is always a better death than suicide via HE or water.
Just to add, there is a bit more of a strategic thought that can go into arty (#2 covers this). Do you support the lemming train to gain a quick victory on that side? Or do you support the weak side that only had 2 tanks to defend an entire flank? I don't use XVM, but still have win rates of 58-59% in my m40/43 and m53/55 after 1500+ games between the two.
#6. I don't CB 99% of the time. Reload times of 35+ seconds plus RNG accuracy equals too much time wasted when the enemy tanks are killing my team. Only possibly worthwhile if it is a map with multiple arty, but only a couple good firing points, greatly increasing your chance of catching a tracer. I still don't CB, but I make sure I move a bit more than normal small movements. An enemy m53/55 thought my arty teammate was hacking since he was CB after the first shot. Of course, the m53/55 was on a map that there was only a couple good arty spots, so it was easy to spot his tracer.
RNG will both bless you with sweet shots, and absolutely let your entire team down when you miss the stationary t95...repeatedly.
Lower tiered arty sucks. The shots will hit for 20 hp on tanks that have 500 hp, and you don't have range. Tier 6 arty is when it becomes decent, at least for American arty.
My favorite couple tanks to play are the m8a1 and t49. Nimble, quick, and decent firepower. And t4/5 games are pretty quick and enjoyable. On the higher end, m103 is nice, and I also enjoy Pershing/Patton. I like having the mobility to get where I'm needed.
Generic advice for new players of WoT: Not only are there scouts/meds/heavies/arty, but each country offers some unique aspects. Some people love the autoloaders of the French, or the armor of the Germans, the gun depression of American tanks, or the Russian bias of Russian tanks. Play around to see what you enjoy, and see what enemy tanks you face to see if you would rather drive those tanks.