I think it sounds great!! And your numbers sound like they will be good for IUI - you have normal motility (50% is the low end of normal) and 18% morphology is low but not horrific (I think they are using the WHO scale, and 30% is normal). Do I remember correctly that your DH smokes? He could probably return his sperm count to normal in a few months if he quits - it lowers count and volume and affects morphology. Also, if he is willing to take vitamins, a regular men's multivitamin, Vitamin C, and pycnogenol should help with morphology a lot. You can add other things if he is willing to go all out, but not all men are willing to swallow a bunch of different vitamins. The Fertility Blend is good, too, but a lot of those require taking a bazillion times a day and are expensive.
Anyway - it sounds like a great plan - I'm sure you will get that

in no time!! Anyway, yay for the HSG, and I know what a relief it is to have answers and a plan of action! You can always switch back to this OB once you are pregnant. Good luck!! Is she recommending a lap to check for endo at all, or just put that off for now?