A good army to beat Karador on impossible with a paladin?

[DGDobrev]

I was wondering what kind of an army + spell setup could beat karador on impossible without getting wiped out easily. I personally consider karador to be one of the toughest battles around, mainly because you start at a serious disadvantage - behind a barricade, with a cursed cross to cripple your army and with enough space for the bone dragons to harass you and a nice crystal that casts necro call once every turn.

In a battle like this I see how the superior leadership of the warrior or the 2x cast per turn of the mage here will make it a lot easier. My spirits are level 19-23, which is a generally normal level at this point in the game. A warrior would have them at higher level I guess.

Right now I'm lvl 24, close to 25 at day 7 (yeah, I'm a bit slow, I know), about to tackle Karador, and I'm hitting the brick wall.

Stats:
Attk: 19
Def: 32
Int: 15
Rage: 64
Mana: 78
Ldrshp: 17092

I also have pretty much every useful spell in my book - spring, resurrection, gift, target, sacrifice, etc. No teleport though... Not a single spell of that kind in my game so far.

I've mastered pretty much everything and went almost all the way down through all the trees - lvl 3 onslaught, own inquisitors, runic stone, lvl 3 archmage/bowmen for more recruits. No destroyer yet, but I can take it, I just don't see much of a point since I'm not using offensive spells at all, and besides, I consider the paladin to perform better as a fighter than a caster.

So...

For starters, the barricade is 500 HP, so even a high-level shoal can't destroy it, as it's 450 max.

2x archer + inquisitor + archmage + green dragon as tank doesn't seem to work very well because the bone dragons easily break through any thorns/walls or whatever I use to slow them down and start harassing the archers.

The ultra power girl party isn't working well either. You must waste a turn to destroy the barricade which allows the enemy to get quite a bit of free hits at your frail army, and the thorns aren't doing much good either. I tried using demonesses to swap the units and give me tactical advantage, but karador uses fear all the time - usually after all my units have moved and I can't cope with dispelling that all the time.

I also tried using a power party of lvl 4-5 units - to not that good effect either. Those 110 Black knights, 800 zombies, about 1500 skelies and 1700 skel archers are a pain in the butt.

I can actually see a way out - get the power girl party back to darion, travel through the mines and go get more XP and a few more levels in Demonis. It won't be hard hard at all, because I can easily own even overpowering enemies with thorns or tank strategy (alternating between the two, depending on the battle), but I hoped to save a few days worth traveling

So I'm just looking for some opinions from the hardcore players who have beaten impossible before I pack my bags and go on my merry way to demonis and/or the islands to get anga's ruby and a few more levels + Xeona