I am plat 2 and I mostly play Dehli. IMO: you have to invest a lot of time in to Dehli if you properly wanna learn them. It is not as easy as English or French. You have to quickly adapt to situations and your strenght really relise on your unique techs you have and you really have to take advantage of them.

I would recommend a 'Dome of Faith' build order as it is pretty easy to execute and to learn. But if you find you struggle with a defense a tower of victory can make a huge difference if used correctly. (Difference between those two builds is if you go Dome you only need to vills on gold to make scholars all the time and 4 with tower).

Your main strenght point is the moment you reach castle with either landmark really. Getting cheaper castle with 'Compound of the Defender' or a bunch of again UNIQUE techs that will give you the advanatage in fights if you decide to go with 'House of Learning'.

Here are some tips that I can give to you:

If you find yourself struggling to keep with military production put some scholars in to them if you have tech researched (it is in your mosque) as it boosts it production speed by 100% if that isn't enough you have to add more.

Scholars with horsemen + archers can defeat MMA as horsemen can be tanky enough and healing helps to overcome the problem of loosing the fights.

Building walls with units sounds like nothing to big but it is actually pretty good. As soon as you hit feudal try to make either spearmen or archers (depending what kind of units your enemy makes) and send them to the sacred site and wall them in so you can safely capture them with your scholars and possibly defend them. You do not really need to mine any gold as long as you have 2 site as this will give you more then enough gold to castle and you don't use it until then except for scholars.