I would go for a hydraulic roller since you plan to spend time at high rpm. It seems like the best combo of performance and low maintenance, from my research. I have something like a 264 comp hydraulic roller in my 406 sbc Gen I (4 bolt mains), in my 79 C20 pickup. It is a DD and tow vehicle. CR is 10.2:1, hyper flat tops (used from old build), forged (blueprinted/trued and re heat treated) crank and forged rods, balanced and blueprinted, full roller rockers, ported aluminum heads, ported aluminum intake, tri y headers, 3" exhaust, etc. It really likes the upper end of the rpm range with the roller valve train. It seems like it jumps up there fast and has no problem hanging out. The old cam was a little bigger but flat tappet and only roller tipped rockers, plus the valve train geometry was crap and the clearances in the bottom end were not good before. I have great torque right off the line and it still pulls steadily up to 5500 rpm. The previous build was not nearly as smooth in the top end or part throttle and it hesitated at 4800 rpm, then took off again. I haven't pushed my 406 past 6,000 rpm, and it stays under 5,000 for the most part. The 600 cfm edelbrock performer carb seems to be limiting my top end and my power when towing at full throttle at 3500-4500 rpm. I haven't towed with the new setup but the last build was pulling 7 inches of vacuum at WOT when towing.
Bigger cubes make the cam seem smaller, so if you have a 350, the power band will be higher. RV cam is kind of generic. You need to know the actual numbers. Roller cams can give you more power with less duration than a flat tappet. I went from a 224/224 at 50 down to a 212/218 at 50 but seemed to gain power. The lift did go up a bit with this new cam. The old cam was a comp 270H magnum. I passed smog with no problem on the 270h cam, but my carb had to be adjusted lean on the idle mixture screws.
All of the different parts to your engine can make a difference on how it will run with a certain cam. My heads have a ton of porting work and are actually bigger than my engine builder would have liked for a low end torque oriented engine. He claims the new cam helps with this. He talked to a guy he knows at comp, to decide on the proper cam. If it hadn't been a smog engine, he would have gone with a bigger cam that he likes for big torque numbers. My heads are the larger size from edelbrock performer and flat tops give me good compression. The pistons are either even with the deck or slightly above. The smaller heads would have really bumped up the compression. Cams have a CR range that they work best with. Big cams need more CR.
My k5 has a 208, 700r4, and 4.88 gears, with 35" tires. The engine is a stock gm crate 350 tbi. It has just a little lower gear than factory equivalent. With the stock engine, it really needed the switch from 3.73 gears.
My pickup has a th400 and a gearvendors overdrive to give it a 0.78:1 overdrive ratio. It has 33" tires and 4.10 factory gear ratio. I can go up pretty decent grades at 2,000 rpm or less in overdrive and the engine has no problem. 70mph is 2300-2400 rpm in overdrive. The engine really likes to run at 2500 rpm.
Your driving will be different. Your rear ratio doesn't seem bad, now that I see you have no overdrive, plus you probably won't be cruising for long periods in 3rd gear.
