I think we've seen some instilling flavor in other classes without crippling their ability to chose what's important with regards to skills. There are all sorts of different kinds of other classes, which arguably a lot of the justification around rogue could be said about as well. In fact a lot of the justification around certain things just sounds like things that a pathfinder hero is.
What is it you want a rogue to do? So far, you've only listed what you want them to NOT do.
Well, despite the cheesy and awkward path of the rogue, I definitely think there is a solid archetype there.
Sneak attack is a solid ability as far as mechanics. I actually like it. It seems hard to balance in some ways, and I know some people were upset with the number of sneak attack dice changing, but you're going to have to ensure balance. I would easily imagine enhancing rogues flavor by upgrading sneak attack to have a variety of debuffs you can apply based on the body parts/features of an enemy(flavored a bit like called shots, but applied a lot like metamagic or paladin's mercies).
If they had more out of combat abilities, I'd have them flavored around
Rogues have always been an awkward class in D&D and Pathfinder. In the original d&d the got the ability to "climb walls, pick pockets, hide, move silently, hear noises, find traps, read languages, and pick locks", something I famously remember hearing someone say "that before rogue came out, every character was trying to do" but became in some ways locked out from other characters. Of a game about exploring dungeons they were the class that was "good at dungeon-ing". Rogues got this power in some senses by giving up the ability to build strongholds.
Giving up an "aspect of play" for another "aspect of play" is a common trope that rears it's head in these kinds of play, but I don't think it's actually a good move to do. Often it's the kind of trade off that isn't really a trade-off (see trading off less used outside of dungeon abilities for dungeon abilities). On the other side you often see players become disengaged and distract able during the sections they're bad at to become overbearing in the sections they are good at. This is often going to happen regardless to some degree, but we don't need our rules systems enforcing this balance.
The three aspects of play, as defined by 5e, are often "exploration, social interaction, and combat". By that, it means that any given section of game-play is going to be about exploration, social interaction, or combat. Combat is generally governed by combat abilities which allow different classes to be effective in combat, while expressing themselves differently and interacting differently. Social interaction tends to be guided by player choice(and to a lesser degree by the "social skills"). Exploration tends to be driven by skill checks, or utility spells.
It seems as though in 3.5 and earlier editions, they were often given more skill points to deal with the fact that the skills they tend to specialize in are split into multiple categories (we can see this with bard as well, given their specialization on lore). Because of this, I think they have been given the reputation of being good at "skills". However this unbalances them in respect of exploration. Instead of choosing what to be good at, rogues just chose everything. Even spell casters, who often are given abilities rogues dream about, have to prepare for the specific encounter they run up against.
The rogue is just "good at everything", or "good at skills" in some ways doesn't even represent an archetype. Barbarians are tough, and fight in a reckless manner, we can see this represented in their combat style. It doesn't make them more powerful in the combat sphere then their peers, it just makes them interact in the combat sphere differently, but not only that but it represents something tangible in the world. Rogues being "good at skills" represents generally "being good at things", something that we see present in the game system(it's called being a higher level). Given the way skills are fungible, we can probably see some of the problems present in 5e as well(The tough and strong barbarian isn't the best class at athletics/grappling, that spot belongs to the bard/rogue due to expertise). Being good at skills doesn't advance rogues archetype of being sneaky or using subterfuge, if anything it actually dilutes the role of the rogue, making them a blank empty everything.
With the raising of power of the "trained" level, I think we're going to see rogues be considered more powerful in this sphere. Characters seem altogether more powerful(or more flat) in a lot of ways. In ability scores and skills you tend to chose 1/2-3/4 of things, usually it seems choosing the 1/4 of things you don't want. Already the numbers seem high, but as far as skills rogues don't chose, they just get everything. Sure, lores exist, but they seem vaguer and harder to use(almost like wises in mouseguard, like an entirely different system).
In some ways, due to historical reasons, rogue often feels like mechanics chasing a class/feeling rather then a feeling chasing mechanics. You have to get additional d6's on attacks occasionally because that's the way rogues have always worked. Why are rogues good at skills? either to be good at a specific set of skills, or to fill the "skill monkey role", something with dubious fluff, and mechanically off balancing effects. We can see this to some degree in the thurge. Was the thurge created because someone wanted to play a religious mage? No, wizards could always be religious, and clerics have always been mage-y to some degree. Was it to play a knowledgeable cleric? Well clerics have always had the ability to pick up knowledge skills and raise their knowledge(and they've often had a domain to deal with it). Nope, someone was bummed that they didn't have access to every spell in d&d and decided they wanted that mechanic with flimsy thematic reasons.
In summation. Please think carefully about the path going forward with rogues. Think about the fluff that rogue should fill, and try and base abilities on that more then what the specific implementation of those abilities have been in the past. Don't fall for trading pillars as a form of balance, or the trap of "just good at x pillar". Don't fall for the abilities that actually make a class more bland and flavorless.
edit: I apologize for any incoherence. I'm tired.