Most definitely. I've played a shitload of BF4 on 360 since its release, it was my first BF game too- coming from a mainly CoD background and rebought it for PS4 with premium when it went on sale in January. This DICE LA's baby, and they've said that while Hardline will still be the "new hotness", they will continue to release content for BF4. I can't imagine there being 5 more DLC pcaks, but we know at least that there will be a community vote for a new map, and Night Mode will be added at some point, along with the occasional tweaks and balances. They aren't just abandoning this game.
I don't know if premium will cover the future DLC, but so far, all 5 expansions are marvelous; I can't imagine playing without Final Stand and Dragon's Teeth maps and content. And since you're just jumping in, expect a metric fuckton of free stuff when you boot up the game, Premium or not.
As for the community, expect a bit of deadness in BF4 during the first few days or weeks of release, but I feel like Hardline plays radically different compared to 4. Since I've played the beta I can tell that Hardline took a few cues from the CoD franchise, making it more arcade oriented, faster paced, more reliant on mid to close range and putting the snipers on the backburners a bit while buffing Pistols and Shotguns and making Suppression far less effective. I personally loved the hell out of it, but it's not for everyone- expect to see people burned by the new playstyle, returning to BF4 in droves; just like what happened with CoD Ghosts. It wasn't for everyone, and so support for Black Ops 2 returned within days of the release. That doesn't mean one is better, people just have preferences and expectations.
TL;DR If you like CoD, specifically Black Ops 1 and MW2, I'd suggest waiting for Hardline since the Beta reminded me alot of those games, but with more flair.
I personally suggest getting BF4 though, it should be under $40 for the Premium Edition at this point, and you'll get all 5 map packs, along with a crapload of Gold Battlepacks that unlock everything from EXP bosts to weapon attachments and camos, less if you forego Premium, but still a considerable starting boost. It plays more realistically, but not enough to intimidate you- but there is definitely a learning curve worth noting to it.