Seph, I always did the same with the Total War series. It was all about the map.
I actually LOVE RTS games; Age of Empires is really what stoked the fire in the first place, I recently replayed 2 and 3 and am looking forward to playing the recent remaster of the first for the first time....ever (I came in with AOE2). But for whatever reason, I never cared for how the Total War series did it. I think it's because you're forced to move regiments at a time. I generally like to micromanage individual units, send these 5 units this way, these five units that way, etc. Also the much loftier system requirements the Total War series has always had, while the rest of the RTS world is generally old hardware friendly, didn't help my willingness to playout those battles. "Let the computer determine the outcome of the battle." was my best friend.
CK2 is another animal. Love the dynasty work. Love that I still learn new things about it after so many years.
Regarding the need for Casus Bellis....I mean, there are so many Casus Bellis. I play a lot of Semien games where I aspire to form Israel, and I have the religious C.B. on anyone in the world, since no one else is Jewish. (I've never successfully formed Israel in the game, as you can only declare so many religious wars on the Islamic nations before you get stomped, but it's one of my long-time goals. Many attempts have been made.) All I have to worry about is my Bad Boy rating.
Same thing applies to the modern Roman Empire resurrection playthrough (where you're refounding Hellenism, latest exp.) since no one else is Hellenic. I think the old way of ressurecting Rome before this expansion though, it was a much bigger problem because Orthodox and Catholic can't declare Holy Wars on each other, even though the Byzantines are really the only Orthodox nation at the start of the longest campaign. Once you end the Schism though, and Catholicism becomes a heresy, the map of Europe opens up.
Now, if you're Catholic surrounded by Catholic it's a problem, but you can always adopt a heresy and those events always pop, just not for the heresy I want usually (I always go for Cathar for female priests and Absolute Cognatic succession).
And yeah, no real battle strategy outside of power in numbers and level of tech. Lack of naval combat, even in the sense that land combat exists, hurts worse though and there are a lot of expansions where it could have been added. I also have no idea how new people get into CK2, the full thing is like $500.
Is it essential to you to see the units on screen? Hearts of Iron has, historically, a much more rubust battle system, although still token based. (Haven't played too much HoI4). It covers air, naval, sea, and HoI2, which I did play extensively, would let you get down to setting hours of the days for your support air raids, etc. I feel like they appeal to different types of gamers, and Total War fans are more likely to play things like StarCraft or C&C, while CK2 players are more likely to play something like Civilization. I play everything strategy, so these categories don't apply to me.
SOLDIER, all grand strategies are intimidating and Paradox doesn't understand user-friendly. I think you'd have fun with CK2. You can always use cheats and just kind of sandbox scenarios; I do that sometimes. I still learn about this minutia here or there in the game that I had previously ignored or didn't understand, and it's 7 years in for me.
Best learning scenario in the game is to play as one of the lowly Irish counts (I think they have one Duke). You're relatively protected, can really interact only locally, have some goals you can accomplish (King of Ireland....maybe Emperor of Brittania?), and you'll learn the Catholic playing dynamics, and Tribal playing dynamics (although you can transition to Feudal) and basic income management. If you try to jump right into playing the Byzantine emperor, you're going to be overwhelmed. And yet, this is what people generally want to do.
So what else have yall played? Victoria 2 is much more politics-driven than the rest of Paradox' suite.