I'm playing a tiefling Duskblade, currently at lvl4 and just about to hit 5th. I'm not overly concerned about perfectly optimising the character, so there's a few things I've take for flavour only. Having said that, I do want to avoid handicapping the character too much.
My plan so far has been to stick solely with Duskblade progression, at least as far as 13th level when I get full attack channeling (which is basically the defining ability of the class). However, lately I've been considering a single-level dip into Crusader. There's a few main reasons why:
Party dynamic. Our party lacks a dedicated healer, instead making use of a bardic aura (which gives auto-stabilise and 1hp heal per round) and a scattering of items (most of us own either a wand of Cure Light Wounds or a healing belt). Crusader would give me Martial Spirit and Crusader's Strike, both of which heal me or my allies when I make melee hits - which I do a lot. There's also Stone Bones which would me DR. Steely Resolve would let me defer a little damage for a round, giving me a better chance to retreat and/or heal before the damage kicks in.
We're also starting to come up against bigger enemies and some of the party are having trouble getting through their AC, so the ability to give everyone +4 to hit a certain target with either Vanguard Strike or Leading the Attack would be helpful.
Plot and flavour. My character has something of a vendetta against the undead, for various reasons including a strong religious devotion. Crusader ties in neatly with that, with powers stemming from a divine connection. I already RP pausing for prayer and funerary rites after major combat, so the 5 minute prayer to ready maneuvers would fit right in.
Prestige options. This is a lesser consideration, but having a level of Crusader would open up the option of Jade Phoenix Mage once I get past Duskblade 13, at which point I could take up to 6 levels in it. This would give me 4 levels of Duskblade spell progression, which is just enough to get me to the highest level of Duskblade spells (5th). It also nets me some pretty cool stances, and a strike that can give me a free Empower per encounter. Most interestingly, it has things that boost caster level of my spells, which is nice.
My only concern in taking a level of Crusader is that it would delay the Duskblade progression. The first level of Crusader gives a +1 to BAB, so that would continue as normal. Jade Phoenix Mage likewise progresses BAB at +1 per level, although I'd miss out on my 4th attack if I took more than four levels of it.
So, the main question:
My main concern is survivability, so I don't mind a reduction in damage output if it means I can keep myself and my party alive longer. I'd also like to boost my casting a little - Duskblades are very much "fighter with some spells", and I'd kinda like to move this slightly toward the middle ground. I don't want to cross over into "caster who can melee a bit" though.
Given the above, if I took Duskblade 13/Crusader 1/Jade Phoenix Mage 6, would I be seriously handicapping my character compared to a pure Duskblade?