Your list appears to be quite valid, but there might be some aspects to consider:
1. Shooting efficiency: running an Arab army myself (although it needs further playtesting), I tend to field spear/archer infantry in units of 8 instead of 6, because 3 shooting dice won't do that much damage. Maybe take 3 units of 8 instead of 4 with 6 bases?
2. What is your plan for the militia? These are terrible (inferior) fighters, but could serve as a blocking unit to pin enemies for a cavalry flank charge. Maybe leave them out for some other choices?
3. Instead of melee militia, consider militia archer skirmishers (cheap, shooty and able to deal with terrain).
4. Armenian Ghulams give a good punch and 3 units of Ghulams is great. Perry do some nice Armenian figures
5. Use skirmishing shooty cavalry to shield your ghulams. The Abbasiya and Turcomans might be the choice to go, although a bit pricy, but effective.
6. Consider the time period you want to play in and your possible opponents! Should the focus lie more on the high medieval/crusades era, then 1250 points is your army size instead of 1000.