As for the crossover, assuming you'll be using an 8Ω DE250, I suggest adding a little more attenuation to the tweeter circuit. Instead of using 25Ω and 16Ω for R1 and R2, use 30Ω and 14Ω, respectively. This will make up for the difference in voltage sensitivity. When using a 2226J instead of a 2226H, scale all values in the woofer circuit to match, doubling the inductance and resistance values and halving the capacitance values.

I also suggest that you don't skimp on the resistors. They don't cost all that much and even if you're using low-power tube amps, it never hurts to over-rate the parts and keep 'em cool. It also allows you to use your speakers with the full amount of power the drivers are designed for without risking damage to anything. There's a lot of dynamic range potential in a speaker like this, but only if all the parts can handle it.