Wow, sorry but all your complaining seems to indicate that you just are not the type of player that should be playing tactical RPG's like Fire Emblem.

The point of it is that you SHOULD NOT be putting your weak defense characters in a place where they'll be attacked by the enemy!!! You can see where the enemy can walk to by selecting them, you can see roughly their level and their attack capability. You're supposed to use your tank characters to make defensive walls around your weak guys to prevent them from being hit.

You got to learn how to use choke points, how to turtle defense until you clear the field of high movement enemies.

Radiant dawn actually has a lot of playable characters and each chapter has different guys but they all rejoin later on in the game so its not time wasted. The whole point of the game is thinking tactically and how to prepare your guys with the best defense. Have the fun is taking the weak characters and through strategy like hurting one enemy for them to kill and then using abilities like shove/rescue/blessings to get them out of danger. Or just use bonus exp.

If you're finding it hard, play it on easy until you learn how the game works. They also put in the battle save for a reason.

Unfortunate thing about Radiant Dawn is that the chapter 1 guys are WEAK. Micaiah is a mage, if you ever play mmorpg's, you'll see the same tactics being applied. And note that swordmasters are not supposed to be tanks, they're high offense, high avoidance, low defense. You just need to learn how the characters and classes work.

Oh also realize that because they added the auto-save feature on normal difficulty, they made it harder than normal. According to people who compared the enemy stats, the US normal difficulty is similar to the Japan hard difficulty.

Just because you have too much pride or think you're badass doesn't mean you should be doing normal difficulty, especially in a game that really punishes you for making mistakes and its your first tactical rpg.

Can we get back to the orginal post where he complains that characters don't stay with you the whole game? I hate that. I spend time getting the first group to an okay level to never use them again? And what about the supports? How are we suppose to build up the supports when people keep disappearing. And don't get me started on how bad the support conversations are.

Look. The game is good. I like it. But lets also say some things need to be improved for next time.

I do have one question. How are you suppose to level up your characters if they can't take a single hit? Normally I try to get one bad guy alone then soften him up till my bad character can kill him with one hit. BUT I am having trouble getting one character alone alot in this game. I am also finding it hard to NOT kill that one character when trying to get its hit points down enough for my bad character to be used.

 They do come back to you later on in the game.  This is actually unusual for Fire Emblem.  If you played Path of Radiance, all the characters stay with you basically once you get them.  There are so many characters in this one (appox 70 or so) that to make sure you try out each one, they're split into chapters such that you are forced to try out new ones. 

It is a problem with certain characters that you don't get back till a few levels in the last chapter but the majority of them you'll have decent play time with.  Trust me, you'll have to play with Micaiah's stupid group again (too many times in my opinion).  This is also the point of bonus exp.  They're put in there so that you can bring certain characters up even if they haven't fought much.

As for leveling up characters that can't take a hit, there are a bunch of tactics you can do.  You can tell from the stats they display exactly how much dmg you'll do to the enemy, the chance of hitting, the amt of damage they'll do back so you know exactly if you have a chance of killing them.  With that info, you can also plan how to leave one enemy with maybe 1 or 2 hitpoints for the really really weak guys to kill.  Once they make the kill, either  shove them out of the way of enemy attackers or have them rescued out of there.  Other tactics are that archers can't counterattack melee attackers, you can unequip weapons on your guys so that they won't auto-kill the enemy if they decide to attack (great tanking strategy).  There are also items/weapons you can custom make that'll give your guys higher chance of hitting and do more damage.   Also it helps a lot once you get one of the herons so that you can have your weak guys attack twice in one round and get even more exp. 

Also keep in mind that in all of these types of games, there are some characters that are just godly with incredible stat growths, and some that are absolute crap.

You can baby the crappy guys a lot but they're still gonna suck a lot. Unfortunately, Macaiah's group has most of the absolute crap people. Fiona, Meg for example are the 2 worst characters in the game. Some of them just aren't worth it, esp when you get awesome people later that are the same class like Brom to replace Meg and Titania to replace Fiona.

 Usually in FE there are characters who's stats start bad, but have amazing growth. Others have good starting stats, but have very little growth. Those characters you mentioned might still be good. I'd have to look up their growth.

Watch the spoilers yes?  Yes maybe?

 Well it was stated a long time ago that all the PoR characters minus a couple were returning so its hardly a spoiler.

You assume Astrodust reads.  He might not.

 Hm...good point.  >_<