The lower levels do indeed get more and better drops. There are other reasons for this I'm sure, but I can explain this one.
You need to better understand the mechanics of farming.
In real life, after several years of farming, you have basically stripped many nutrients out of the soil.
When this happens, you have to let the field lay fallow for a year, so that the nutrients replenish.
This is true no matter what sort of fertilizers you use.
The same is true in the game. As a person who does alot of different farming in different areas, I have seen the effects of overfarming.
When you are new to the game, you have obviously not spent alot of time working any particular area.
The field is new and fresh. However, once you have achieved LDoA ( especially if it was DL'd),
you have basically farmed the shit out of The Northlands.
If you leave it alone for a couple of months your drops should improve.
The number of people farming or hunting an area also makes a difference.
This is the reason why bots are so despised in both pre and post.
The more players continually farming an area, the less likely everyone is to get decent drops.
Your best farming/hunting options are when Ascalon is quiet, after a respite.