The best negotiating tactic I have discovered is knowing what they paid for the vehicle and what factory incentives are being offered.
In Canada I use this site....
It is a great tool to keep in your back pocket. If you can negotiate down to 5% or less of what they paid for the vehicle you are doing pretty well and you know you aren't leaving extra money on the table. It will also tell you what factory incentives the dealer is getting at the time of the sale.
You must have something similar in the US.
On the daily driver side of things we actually find our F250 nicer to drive than the F150 we came from. The F250 provides more visibility and less blind spots. Yes we spend an extra 3-4 dollars on gas for every 100kms we drive empty but pulling mileage is about the same and our comfort level is much higher.
People always think that 3/4 or 12 tons are a lot larger as well and I don't think they are. Here are the stats for a F150 compared to a F250. Both are crew cab 4x4's with the 6.5 foot box.
F150 vs F250
243.7_______246.8 overall length
79.9________79.9 width no mirrors
105.9_______104.9 width with towing mirrors
Honestly it is a wash for me unless the height is going to get you and you need to park underground. The F250 is actually narrower than the 150 by 1 inch.
Although if you are coming from a short box half ton the length difference is more significant.