You do not get gametime. When classic gold comes to server soda it pertains to many WOW players are on every kingdom. I play on a realm that says complete a whole lot, but I never had to sit in a queue to log in there, or had trouble creating characters etc.. I would advise choosing a top or complete people realm, and stay clear of"New Player" realms - I have heard some not great things about them from different people joining them. Those realms change an effort to boost their inhabitants I am not sure. It doesn't matter that a realm has a high population if you're on the minority faction, a few servers are actually skewed towards alliance or horde. So barren can be felt by a number of the large servers only on account of your faction. I think what realm you play is important to your experience.
I recommend playing on a high or full population realm, I have alts on"medium" pop realms but they feel like they are left handed. I play on a RP realm my guild and me are not primarily roleWOW players. You don't need to join one although I enjoy the opportunity, and the benefits of being on a RP realm. Check if you're going to be a part of the dominant faction on whatever server you could combine, or whether it's split fairly. I will not stop you from purchasing bfa, however the testing of this new expansion is in progress and it's set to launch. I know I personally wouldn't be purchasing the bfa growth the growth is sort of finished.
Each of the content is published and it might get harder and harder to get the full value from your subscription as busy WOW players believe themselves done before shadowlands comes, people are disinterested in doing the old bfa articles etc.. I don't think checking out the material and purchasing gametime - but this may largely be single player content. If you get BFA now, you would need to purchase shadowlands later this year to play that as well. Ironically it is the bfa content that is quite interesting to play so it's up to you. You could use up a subscription to lvl 110, and test out WOW Classic in case you're ever interested.
I am not familiar if you can play at the"pre-patch" of shadowlands with no bfa expansion but that might be a good time to jump in. That's usually a month before the actual launch of the expansion. If anybody could confirm that you can play shadowlands prepatch with no bfa that cheapest wow gold would be useful to understand. You do not get gametime. Decide on a large or complete pop kingdom with an even supply of the factions, or one where you combine the dominant faction. Remain clear of"New Player" realms, and consider an RP one if you are interested in roleplay. Consider playing without the bfa growth until shadowlands comes out.