My purpose for writing the Isles of Maga setting is to illustrate a world that allows for epic adventures, balanced with a nuanced understanding of moral conflict. The major points are these:
Pure Evil is Rare: Generally, your characters will not be fighting "pure evil" villains. Even the most apparently misanthropic Demon Lords actually have complex motivations. Races that are generally hostile are either animalistic, or have personal reasons for attacking you. Communication may solve more conflicts than brute force, although fighting will still be necessary in a tough situation. This point is the reason why "Detect Evil" and similar spells were renamed, because evil is not a simple quality or a substance to be detected in such a sense. Note that this does not mean the population of Maga agrees with this sentiment; many probably do believe in and fear truly evil things.
"Evil" Gods are Close; the "Good" God is Distant: The existence of Demon Lords is undeniable, and they do hold power in this world. However, worship of Gora is the only recognized legitimate religion in Maga, but there is scarce evidence for the existence of Gora.
Arcane Magic is Regulated: Anybody can use magic if they learn the correct incantation. However, there are only a few practitioners of magic in Maga. The Mages Guild specifically exists to sanction and regulate the use of magic, and to limit public access to magical knowledge. It is illegal for non-members of the Mages Guild to cast magic, but some do it anyway. Note that this does not apply to divine magic, which is cast through devotion to a higher power, making it more difficult to regulate.
Demon Lords are human-like: Demon Lords are not very different from humans. They can be petty, jealous, angry, or sad, and this will govern their actions. Look at Greek mythology for a better understanding of what I mean. Out of jealousy Hera tried to kill Hercules, a son of Zeus (her husband) and a human woman. Two important human-like things are present here: gods can feel lust (and cheat), and gods can feel jealous (and get revenge). While Demon Lords are somewhat more detached from our reality than the Greek gods were, they are still not abstract entities.
Racial conflict: Racism/Speciesism exists both on formal and informal levels. In particular, the Bulgars and the Magafel have a long history of animosity towards each other, dating even before the colonization of Maga. Furthermore, beast-races are seen as less than the races of Men and Fel. Many other sentient races such as Orcs refuse to integrate with the Republic out of principle, due to believing it has no right to exist.
Cosmopolitan world: The races of Men, Fel, as well as Lacertineans and Felidineans hold citizenship in the Republic, and are well integrated in the major cities. Even in a predominantly "Kelt" village, you may see one or two members of the beast-races. Even in the "Bulgar" capital, you are likely to see a few humans and halflings along with them.
Ocean travel: Because the islands are quite small (a typical size being 500 or so square miles), most locations on the same island are a day's travel at most. A distant location will certainly need a boat to reach, making water travel critical in Maga. Furthermore, ancient Lacertine-built structures from before colonization dot the ocean floor, giving possibilities for extensive underwater exploration.