First of all, comparing a wizard to a fighter without buffs is like comparing the fighter to a wizard who does not cast spells. Buffs exist, and they tend to work extremely well with fighters. Who cares when you cast enlarge person the wizard? Second, the same effect cannot be achieved by buffing an NPC warrior or the druid's ape, unless you can figure out how to supply them with an extra half dozen feats and a suitable selection of magical weapons, armor, potions, and wondrous items. Third, reach weapon + magic oil = reach whenever you need it.
On other words, "If the party is in a D&D game." Fighters get buffed, and buffers buff fighters. Creature immunities... guess what? That's a fact of life. No one tactic is going to work on everything. This is not handicapped, any more than flying creatures are somewhere handicapping a fighter who focuses on melee.
Poison - This is a non-point. Of course it can fail. I don't see a lot of neutralize poison floating around. Fighters can often shruff off poison entirely.
On Fighters and buffs/magic
I think this boils down to personal preference. 3e fighters don't bring anything to the table outside of being the target of buff spells. If your big advantage over an NPC class is that you have more money to spend on magical gear, that's a problem. Classes from tome of battle and 4e meleeists actually have unique abilities that they bring to the table. Do they still need magic items to be better? Yes. Still need the wizards to buff/debuff? Of course. But at the end of the fight, Wizards say "Thanks for bringing something that I could not easily replicate with a spell or two (marking, different abilities from ToB). While in 3e its "Thanks for being the target for my buff spells because otherwise you would have been dead weight."
Like I said eariler, magic is the sole power in 3e. As a high level fighter, I want to be feared because of my peerless martial prowess, not because I am wearing more magic items than the enemy.
Quote
8th level, with a 9th level dwarven scout. Honestly, I expected them to all die, as they kind of rushed to fight the lich rather than taking the path I had in mind. But by round three, they figured out how to overcome the DR, and only one character was paralyzed. The scout took a morningstar with magic weapon on it and closed with the lich, each round tumbling around him and readying an an attack to interrupt his spells, while the wizard peppered it with magic missiles.
end quote
I am still unclear how ready actions is this effective.
I ready an action to attack if the lich casts anything.
The lich 5 foot steps then casts, your readied action fails to go off. Unless you are wielding a spiked chain since that is the only weapon with reach that allows you to threaten adjacent squares.
or
I ready an action to five foot step after the lich.
The lich 5 ft steps you move with him, and then the lich casts defensively. Congrats you just sacrificed your turn in hopes the lich rolls a 2 on his concentration check. (unless you have the mage slayer feat, but that's in a splat)
Also, in both your example fights, the casters made or broke the encounters. The cleric got around the DR with a spell and the party suffered terriblely once their healing got knocked down. It's the magic arms race or "Magic must defeat magic". To get around certain spells you need the counter spells. You can't beat invisiblity with a spot check you need see invisibilty. No amount of damage will ever break a wall of force. You need disintigrate. Arcane lock can only be opened by knock, it doesn't care if your open lock skill is +100. If it is not magic, no one cares.
