Until the new codex dropped, BA, DA, DW, and RG were the four strongest marine builds. If you used Girlyman, UM could also compete. In fact, BA were some of the fastest marines, with ways to allow their jump troupes to move twice, etc. They were very likely to make it into melee.
The weakest mono marines were BT and GK. BT because no psycher support, only 1 denial strategem in a game that has very nasty buffs and mortal wounds crammed into the psychic phase, and a chapter tactic all about getting marines into combat in an edition where marines struggled to hold their own if you didn't pay out the butt for thunder hammers. GK, on the other hand, are just too expensive. That's really the primary thing that's been holding them back. They pay a huge cost for being psychers and can't do enough damage or survive on the table long enough to earn those points back.
As a BT player, it feels a little silly to see BA players complaining that they've been left behind. We all know BA will get a rules update. Hell, just two months ago you were the gold standard for mono marines, with some of the best strategems and cheesiest combos we could field, not to mention the flat out strongest unit SM have access to in the form of your flying psychic dreadnought. You'll be fine. Your rules are coming. Let's chill out and let IH have their time in the sun. I'm so happy for them. If any chapter deserved a meta boost for exposure, it's them.
As for other books? DG are still ridiculously strong. Eldar are still ridiculously strong. Guard are still ridiculously strong. Thousand Suns can still throw out enough smite spam and daemon troupes to kick anyone off the board. Slaanesh Daemons still have access to the flat out best new daemon units that have been released. T'au can still shoot you off of the board, though the increasing number of ways to ignore overwatch should be monitored, as it's reaching a critical point passed which they're going to start struggling.
As of now, the armies that most need a boost are Khorne Daemons, who have nothing going for them other than DPs and Bloodletter bombs; Necrons, who need a face lift in several key areas; GK, who struggled for all of 8th and deserve priority over factions that have had a good run in 8th; and sisters, who are going to get their book in November.
Finally, the neglected chaos Marines need to be brought into line with the rest of their brothers. DG and TS will get updated, but BL, WE, NL, WB, etc etc etc. They need a new codex that isn't a sham, and their own mini books. I wouldn't be surprised if that comes along some time next year.