This is a disgrace, all the while admitting it as nonchalant, as you did is equally simpatico... anyway you HAVE got to play both Raiser's for Koshiro's OSTs alone. The first is even more iconic and if one holds in mind, that it was a launch title, then the more stunning it becomes. Of course, if you didn't played it back then, you won't feel that nostalgia kick and chances are, both games might even disappoint you. Let's hope not.
Regarding the sim part, many feel that this is the true ActRaiser and they despise the second game, which let go of it. I see it the other way around. The sim is nice, I definitely love the kindness it radiates, but am more attached to the action levels. Good thing is: the game lets one decide, weather or not to play it with the sim or, just action oriented, without.
For me, the second Raiser offers the better God experience, with the story unfolding with each stage beautifully. Conceptually it's more compelling, too. But that's just an arguable and very subjective opinion. The majority loves the first part's sim more, than the actual game. And I fully understand it.