Well, obviously WotC could suddenly decide to release virtually anything, but I don't see this as 'early days' of 5e! This is 3 years since the official release of the game, is it not? I mean, 2.5 years. This is the point in 4e where it was 2011, the PHB3 had been released IIRC, most of the * Power series of books was out, and essentially the game was feature complete. Around this time WotC must have begun working on Essentials, since it was released in 2012.
So, I would expect that 5e is feature complete and mature. Beyond that every year that goes by and sees more material released for a game reduces the chances of any significant additions and revampings, short of an edition-roll-like event (IE like the release of Essentials or 3.5). I don't see anything like this in the cards for 5e. WotC doesn't have the staff, has evinced no interest in significant further 5e rules development, etc. Given the depth of the undertaking I feel entirely confident in my belief that no reworking of 5e in the direction of being 'more tactical' will ever happen. If it does, it will herald the release of a replacement version of the game, not just some supplement. This is exceedingly unlikely in the near to mid-term.