New tanks, new countries, new HD client since then. Easier to progress since then with daily missions (first 3 can reroll eveyr 4 hours). Extra benefits for progression if you have a premium account.
Also, blueprints introduced which let you unlock xp of each tank (not modules), making progress quicker. Get those mostly from daily missions plus other events.
"Battle pass" is a 3x3 month event each year; we're close to finishing 2nd event this year (end August), so good to accrue points ASAP for this event to get the benefits (you get free bonuses without paying, but can pay for extra benefits if you want).
1.18 coming out soon, with a new map, and adding Italian TD tech tree. Also will be tweaking existing tank's specs.
Tier 8 is infested with premiums now, and they've started with a couple now on tier 9. At tier 8, progetto and bourrasque are most popular. At tier 6, M40 is most popular but will finally be nerfed shortly.
Tech tree was revamped, with quite a number of well known popular tanks hived off to a separate "collector" section so they're not part of the tech tree flow any more but can still get if you want them.
WG 12th birthday coming up later this month and there will be discounts then (including the first discounts on collector tanks ever), so if you want to buy any tanks for credits, wait til then for a bit of a saving.