Before I make any more decisions, I need to stop and think about the general tone of the game. What is the design goal? Am I looking at something which simulates Sword & Sorcery fiction? Or perhaps I'm looking to play games of historical fantasy? To that end, let me look at the examples given in the fantasy adaptions section, and the later WRG game Hordes Of The Things.
The army lists they had hoped to do included, "E.R.B. Mars, Middle Earth, Kregen, Novaria, Gor, Dalarna and similar places". Hm. That's a pretty wide range, but it seems to focus mainly on the Sword & Sorcery, pulp side of things. There are specific entries for airboats and radium rifles in the fantasy conversions. In HOTT, we find lists for (or mentions of): Moorcock, Pratchett, Homeric Epic, Arthurian Epic, Carolingian Epic, Irish Epic, Norse Myth, Arabian Myth (including Hollywood Arabesques), Persian Epic, Japanese Epic, Aztec Myth, Hyboria, Barsoom, Spenser's "Faerie Queene", Novaria (L. Sprague de Camp), Fletcher Pratt's Well of the Unicorn (the "Dalarna" mentioned above), Kregen of the Dray Prescott novels, Deryni, Tékumel, Steven Brust's "Vlad Taltos" books, Glen Cook's "Black Company", Egyptian and Chinese semi-historical, the Renaissance (with Da Vinci inventions), and even Napoleonics! Amusingly, I note that WRG had shied away from Gor over the intervening decade, but also dropped Tolkien from the list (probably due to rights issues).
Whew. That's a pretty wide range, indeed. What I get of the sense of it, though, is that the main thrust is toward a sort of heroic, pulp fantasy, but one that treats heroes as only slightly better, in terms of powers and ability, than the common man. So, basically like early D&D. That's a pretty easy choice, then. I'll be keeping that tone in mind as I make design choices.
Happily, at least at first, I don't have to make many huge design choices, though, since I'm still looking at figuring out a way to play WRG Ancients and Medieval, just with single, individual figures instead of units of up to 50 figures with each figure representing 5 or 20 individuals. Many of my design choices are already made for me.