Original Post
WEED
Looking at Lincolns I would say that it is very north base and the weed field and processing in my opinion are very close together. However my idea makes you travel around the island a bit more and definitely shows the change in money. From my location, if you sell in Agios then you get the least and you get more in Athira.
Here is the field, I added the buildings to make it look more worn down:
http://i.imgur.com/JdtS3YQ.jpg
Here is the processing, again I made this myself:
http://i.imgur.com/OLk4S9g.jpg
http://i.imgur.com/Twv7Ljs.jpg
Here is the map and route:
http://i.imgur.com/0Ag7FuH.jpg
Im going to get to work on the others. I have an idea for meth which I will explain once done.
Time: Roughly 1Hr
To Fill Hemmt: 15 minutes
To get to Processor: 12 minutes
Process: 20 minutes
To the Dealer: 15 minutes
Price for full Hemmt: 1 Mill (after restart)
METH
My idea for meth is very run down away from city's shady business. because police always want to do a meth bust. So I found remote locations to the right side of the island and then added some tin fences and so on. First you collect your ingredients from the shabby house, its free to get. Then you head to the meth dealing compound. Now here is my idea, if you do this without learning the "Walter White" skill then there is a 2% chance of the lab blowing up and killing you as you are untrained.
Here is the shabby shack:
http://i.imgur.com/DSH7Rh1.jpg
Here is the shabby compound, with the 2% chance of blowing up:
http://i.imgur.com/JJEsDk8.jpg
Here is the route:
http://i.imgur.com/uvyLLhK.jpg
I thought for this one that I should use the right side of the map like Fry said. However this is my idea for meth.
HEROIN
Heroin is a relatively good way of getting money in terms of low risk and repetitively good reward. So I thought for this one why don't you use the island at the bottom. The processing is in the middle of no where, however a few things should be done such as a raised price due to the length of the run.
Field:
http://i.imgur.com/YfLmrvU.jpg
Processing:
http://i.imgur.com/9IJeZUt.jpg
Map:
http://i.imgur.com/jUAnUqd.jpg
This run will need a refill of the tank, people will usually spawn at Agios if they want to do this.
COCAINE
For cocaine, I feel this should be one of the ones which sells for the most. This goes from one end of the map to the other just like a while ago. The custom build processing is in a church to make it eary.
Field: (Its a field, obviously)
Processing:
http://i.imgur.com/1VyH3ks.jpg
http://i.imgur.com/nTLq8DS.jpg
Map:
http://i.imgur.com/D3dtu3y.jpg