There isn't really that much difference in terms of how much a hormone will dissolve. Besides, you generally don't want to max it out as that most certainly will lead to painful injections. For cyps and enths stick to around 250 mg/mL. For acetates and props stay at or below 100 mg/mL (my preference is 75 mg/mL).
In term of viscosity, there are other oils that are "lighter" such as grapeseed. This does not equate to better though as most of the others tend to have preservatives which make for painful injections. IMO, it is best to stick with cottonseed or a high grade sesame.
Chemo