Here's how understand RPG in a nutshell:
1. You have a character with bunch of stats that determine it.
2. You're able to manipulate those stats in the game (to shape your character).
3. When you do talking choices, the game code does your stat check to determine the outcome (karma, guild, alignment mechanics etc).
4. That outcome affects the story progression, consecutive NPC dialog etc.
SC2 has only (4) in regard to the side-story.
Who cares about the physical name "stats"? You can affect many stats in SCII, just in a non-traditional way.
You want more HP? Build a crew pod, just like I said.
What does the willpower stat dictate usually? Mana regen. Shiva Furnace. How is adding 2 Shiva Furnaces different than adding 2 to your willpower stat?
What about your aim stat? % chance to hit? Come on, Hunam, think bigger. Auto-tracking system. 1, 2, or 3 of those are huge upgrades to your THAC0.
And your defense? Sacrifice some HP, by putting a point into defense instead - Point-Defense System. It's the same thing.
I'm NOT talking about traditional RPG loot. I'm not confusing RPG with upgrades. I'm translating the game mechanics in a more meaningful way.
You want a different playstyle?
Well, a warrior would charge in light a Dreadnought. But a ranger might play like a Spathi Eluder - constantly evading and staying out of range. A thief would need to cloak and get up close to backstab his enemy - like the Ilwrath. These are all valid comparisons to a playstyle. Who cares if you're not locked into being a friggin druid because you chose that option on the character screen. It's not like SCII has the typical druid power of thorns to attach to and slow down your enemies... oh wait... that's the VUX.
As for your "talking choices" point - why is it more organic to use a stat check to determine an outcome, rather than saying what would be the RIGHT thing in a conversation? There's a million moments in SCII where your dialogue affects the outcome of the game WAY more than having put 17 points into speech, so you can convince the shopkeeper to give you 5% off his price. SCII does it in a way where you have to actually choose the dialogue options that would help, rather than seeing a dialogue option onscreen, having your charisma be 2 points too low and not be able to say the words that are right there in front of you. It's a little silly, buddy.
And you'd be hard-pressed to find a game that has more weighty decisions than Star Control II. Entire races live and die based on how cleverly and successfully you helped them.