Obviously those who are advising against Ranger are doing so for reasons other than Gameplay; Horde Breaker means Ranger has more attacks than Fighter at all levels below 11 or at worst the same number. Hunter Ranger scales better with available damage sources, both gaining earlier access to stat dumps (Sharpshooter), better access to advantage granting conditions and effects (including but not limited to ensnaring strike), and better endgame gear support. Enhance Leap is an incredible mobility tool, you get heavy armor proficiencies, the list goes on and on. I'd definitely recommend Hunter Ranger over Warlock, especially if doing Warlock straight up.
That said, Warlock synergizes well with Ranger (no save push effects line up enemies for Horde Breaker), and pushing folks around is a good time so I don't hate having one in the party by any means. Personally I like Warlock 6 / Paladin 6 for "free" (short rest recovery) smites of reasonable power. Storm Sorc is undoubtedly more powerful than an EB based Warlock, but there's no universe in which Fighter is more powerful than Ranger. Hope that helps.
