Ok here goes my 2 cents ...

1) I wouldn't say that ramping is better than straight sets or vice versa. I would say that using the same weight is much easier to track progress from week to week. For this reason I would suggest the constant weight method to you. I would also suggest using small increments (5lb ... 2.5lb if you can find 1.25lb plates). This may seem small but it will catch up with you over time ... trust me. The longer you can sustain the "build up" the better your results will be in most cases.

2) Nail down the basics first... which also leads me to a question. Why not deadlifts?! They are a very important lift for all around body strengthening/thickening.

3) I say keep bulking as long you are gaining muscle and keeping your fat within reasonable levels. If you can do this continuously ... then great. I don't think there is a time limit. Just don't let your fat levels get out of hand because it becomes harder and harder to take it all off and you'll gain a bunch of stretch marks ... etc

4) If you are 20% bf then you should consider dropping some fat. Have you measured this or are you estimating?

As for the question ... A defecit is a deficit wether it is created by cardio or by diet. I would say going into a deficit via cardio addition is a wise idea. It's never a bad idea to keep your cardiovascular health up. Overdoing it on cardio will have negative affects on weight lifting however.

I hope this helps. Anyone else can also feel free to counter my opinions.

IW