[Lots of discussion on Krynn series snipped..]
For your FR run:
You can have a maximum of 3 Rangers in the party. I don't think this is actually documented anywhere, but the limit is there. Remember also that Ranger/Mage duals can cast spells in armour. I can't recall if this is mentioned anywhere either.
You will need a Cleric for healing purposes. It is practically mandatory. While the Paladin can take over later with his spells, he won't be getting those until level 9 and it would take a lot longer before he gets enough to be useful, by which time you will be dualling him to mage or what have you.
One way of playing is to use 1 Paladin, 3 Ranger, 1 Cleric, 1 Mage. Get to whatever level you are comfortable with and dual the Paladin and Rangers to Mages. The Mage and the Cleric should dual together or close together and exchange roles. That should keep you covered with firepower and healing at all times.
A small writeup on reflections of Curse and SSB (POD still pending, I don't expect much surprises on that front):
I ended up skipping Pool of Radiance, because it does not offer paladin or ranger as an option, and I didn't want to resort to hex-editing the characters to a different class in Curse.
So I started Curse with 1 paladin, 3 rangers, 1 mage and 1 cleric. Dual-classed one L10 ranger (after Zhentil Keep) to mage and did some grinding so the mage obtained L11. The rest I left to be dual classed in SSB.
The most significant consideration when doing dual-classing is the timing. Section 5.4 of this
https://gamefaqs.gamespot.com/pc/564786-curse-of-the-azure-bonds/faqs/78365 really excellent guide discusses this. You need to avoid too many characters being too weak at the same time. You also want to to use up the experience in each game with level restrictions in mind (Curse provides about 500K, though I grinded to 900K, and SSB about 2,5M additional xp without heavy grinding). So a lot of SSB xp gets wasted when transferring to POD unless you dual class in SSB. Also the typical level cap in SSB being 15, you need to switch at the latest at L14 if you want to get the old abilities back already in SSB. And you probably want at least some of them towards the end.
In SSB (played with Champion difficulty) I switched the mage to cleric, and cleric to mage when both hit L14. This was relatively early. I think they were about L8-L9 when the paladin got to L13 (two attacks) and I switched it to mage. A little bit further on I switched the remaining two rangers to mages when the rangers reached L15 (so I could get two attacks eventually in POD). 5 simultaneous second class developing characters can be pulled off in SSB because the NPC Vala is a decent warrior and completemented my 1 ranger that had been unlocked in Curse with this in mind. Very few monsters in SSB are magic resistant so 4-5 characters throwing fireballs and ice storms compensated for the weak spot in warrior capacity. Towards the end (during Castle dungeons) my paladin/mage got L14 mage and unlocked the paladin capabilities and rather soon both mage/clerics got unlocked as well. In the end L15 rangers had obtained L14, close to L15 as a mage. This way when I start POD I will have unlocked or will soon unlock all dual-classed abilities and continue to develop as 5 mages and 1 cleric. (Mages are very useful as a second class due to having huge amount of HPs and fighting capability from the first warrior class, and getting more deadly DBFs towards the end game.)
After completing SSB I noticed I needed to get some equipment for the two upcoming ranger/mages from the vault, but after completion, everyone was already in victory celebration. So I may need to reload before the final fight to obtain the equipment and maybe also do some additional XP grinding for POD. There are many spots in SSB where you can get 10-15K xp by fighting giants and such battles are over very quickly (a fireball or two and then autorun with quick). Maybe I'll do some because I don't recall how easy it is in the beginning of POD (need to get some 400K XP to unlock the final two ranger/mages).
