In a nutshell, here's the best guidance I can give on cast iron based on my own reading (some here!) and experience (I was not a cast iron fan for a long time).
is my favorite oil, by far, and I've tried a good 80-90% of the oils I've seen recommended. (It may be interesting if you don't know, but the manufacturers I'm aware of used soybean oil as their "pre-seasong" finish.)
A very small dip of my finger into the grease (small, dedicated container for cast iron seasoning) gets sufficient amount of grease to slowly, thinly (which is ideal) coat the entire pan (top, bottom, rim and handle) without overdoing it. The rate at which the fat melts off my finger onto the pan is just perfect. And the smell is much nicer than any plain oil too. Mmmm.
Further, I think the impurities naturally in the bacon grease lend themselves to a stronger finish in their final form as carbon. Last, the time and temperature of the oven can be much less this way IME. I turn the over on for 1 hour at 450ºF with the feshly coated pan in the oven cold. I shut it off after an hour and leave the pan in until cool - usually overnight. I've almost never had to repeat the bake cycle since doing it this way.
Using too much oil is extremely easy to do. For example, coating a pan with a few drips (or dime or quarter-sized spot) of vegetable oil, then wiping it down thoroughly with a clean paper towel (or three clean paper towels) is guaranteed to be way too much oil. More than likely it will run and create a thick layer somewhere inconvenient that becomes very sticky instead of drying hard.
Using too much oil can work in theory I think, but it will take an insane amount of curing time in a hot oven - maybe 24 hours or longer at 450-500ºF - to get through the long sticky-phase. Even if you don't end up with that much, it will still take you longer to finish the seasoning in the oven and require a higher temperature than if you use bacon grease as described.
If you have a pan with a finish that you're unsatisfied with, I would set you over to the max temp is will go (usually 500ºF or higher), leave the pan in there for at least an hour, maybe a few - burn the old coating down to carbon. You can wash this off and start clean with the bacon grease method. After 1 or maybe 2 seasonings it should be pretty non-stick and keep getting better with use. Keep it out of the sink religiously until it's pitch black and shiny, then it will even be able to resist light washing.
Last thought is on people's snobbishness against rough-cast iron like the Lodge stuff. I wanted a griddle for pancackes and eggs. Simply due to good availability(no other cast iron is for sale locally) I picked up the Lodge Round Griddle.
If you can imagine it, that rough-cast iron griddle is now my favorite omlete pan - it was so smooth after just one seasoning and a few rounds of cooking that it works exactly like those cheesy teflon coated pans you used to see in TV commercials. If you like the extra-smooth polished pans, that's fine. But it might be your seasoning method that's keeping you from also liking rough-cast!