Field Marshal for me as well.
I'll probably never use the extra perks like the 3D models (I'm a counters guy), but I'm confident that I'd have bought the extra DLCs anyway, whatever they may be. Plus, I love the HOI series and although I wasn't exactly thrilled with many of the design decisions with HOI4, I trust Paradox. Nobody makes the kind of games they make and nobody is so responsive to their long-term fans. The games they produce (particularly the HOI and Victoria series) give me far more enjoyment than those of any competitor and are difficult to produce. I want HOI4 to be profitable so that Paradox can continue to develop the series, and buying the "premium" version is a way to show my appreciation.
In my opinion, Paradox has always been reasonable with their prices, especially given that their core games are so complex that their market is a bit of a niche. That's not to say that they will always get my money if they start to turn evil, but over the years they have built up an tremendous amount of goodwill and it would take a lot to turn me away from being a loyal customer.