Keeping heat consistent in grill

I have a few specific questions about keeping heat in the grill. It’s a common question in this Reddit and I’ve looked at many of them and tried different methods. However I’m still having trouble getting my grill hot with the lid on and indirect heat.

I always start with a full chimney, wait til charcoal is starting to turn on top. I dump and cover for 10-15 mins. Usually coals go down in temp but the grates are hot. I keep the top vent mostly open with the lid on but have tried keeping it open based on advice from this sub.

Recently I’ve been trying to cooked indirectly then finish over the coals but it seems that after a few minute most of the indirect side is barely hot. I’ve managed to save most cooks with direct heat.

Is it possible I’m spreading the coals out too much? Should I be maintaining a more close “pile”?

Also could my placement of the grill be cause issues? I have it on the ground near my deck steps. Air flow is seemingly fine but should I move it close to the center of my yard?

Thanks for the help yall!