Sorc/Pali or Sorc/Pali/Monk

[Sierim]

For a while I've been playing an 18/2 Sorc/Pali. Originally this was because I prefer to only fail saves on a 1, but with the release of epic destinies (and the fixes that followed), I now have a toon that never fails Fort/Will saves. Now I'm debating adding evasion. My question is this: what do I lose by dropping 2 sorc levels?

Now for more details: This is not a Tukaw build; it is a pure caster with freakishly high saves. In addition, this is a dwarf sorcerer, acid/conjuration specc'd. Why? Because I can. I have several warforged sorcerers, and while they're better at self-healing, I'm a sucker for making "gimps" that are as strong as possible. My planned twists are Eternal Lay on Hands (yes, I can scroll heal, but that's risky in mid combat), Impregnable Mind, and Conjuration School Specialist.

From what I see right now, I gain/lose the following by switching to 16/2/2
Gain
2 Monk feats
+8 Hit Points
+2 to all saves
+1 Conjuration DC (with toughness moved to a monk feat, opening up GSF:Conjuration during heroic levels)
Evasion

Lose
1 MCL Acid
4 CL/SP Acid
2 CL/SP general
1 DC to all non-earth spells
1 level 7 and 8 spell slot
9th level spells
T3 Earth Savant abilities (Earthgrab and SLA Acid Blast )
+1% Acid crit chance, +10% crit damage.
~300-400 SP


My question is whether that's worth it. Earthgrab and Acid Blast SLA are a massive boon together, especially when joined with Solid Fog, but with the monk levels I'll be able to thumb my nose at most enemy evocation/conjuration spells while getting a slight boost to my primary DCs.

Additional Information:
Intended PLs:
2x Sorcerer (already have these)
3x Druid (my sorc likes to run around with a chunky Dense Earth Elemental )
3x Cleric
3x Wizard (FtS/Trap the Soul)
3x FvS (same as wizard)
Possible:
3x Artificer (UMD is always nice)
3x Paladin (is the healing amp worth it?)

[korsat]

If you really want evasion just go 18sorc/2paladin/5shadowdancer. I think the trade-off if bad, expecially for a non-wf.

[Sierim]

I considered using the shadow dancer capstone...for about two seconds before rejecting it out of hand. Two levels of sorcerer might be worth the trade, but an entire epic destiny is certainly not.