Steering effort for manual 16:1 - should it be this high?

It helps with good steering return as well, which is also a good benefit to have racing. That's what causes the wheel to want to return to center. Positive caster. But, a lot of serious road racing vehicles do run very low and even negative caster. It all depends on what you're doing.
Lots of good information here, I would like to add. The tire size here seems to be the largest downfall in this app. I have a 72' Dodge B-300 van that I installed TA G60's on a 15" US-Indy rim(special ordered). About every 3 years I need to have the frame at the gearbox welded, due to cracks. Never had that problem with the stock tires. The wider tire takes much more effort to move then the thinner ones. I like my profile of the van, so this is what I have to live with. Enjoy!!!!