340 Cam Comparison

The things that makes the bottom end soft are a low Dynamic compression ratio,and/or a late closing intake valve which traps less of the inducted mixture at lower rpms . Once the rpm gets up, inertia takes over and the late closing intake is no longer a factor.
Low cranking cylinder pressure can be low because of several factors. Forgetting ring and valve problems, the obvious things are; a large chamber volume compared to the swept volume, and a late closing intake; and/or a modest swept volume to start with.
The 340, at low-rpm, is already slightly handicapped by it's modest swept volume of 696.36 cc per cylinder, and it's short effective stroke when a late-closing big-duration cam is chosen. This all goes away at high rpm, so with an automatic and a hi-stall, you can get away with modest cylinder pressure.
But on the street, with a 2.66 low manual-trans, no TC, and 3.55s, @3600 pounds, that will get very old very quickly. So yes; with a big cam you will be slipping the clutch like an old 5.0Mustang. But what's worse to me, is with an 700 rpm idle, the slowest you can drive with 27" tires is about 5.9mph. And that's if the 340 makes enough power to pull itself smoothly down there.
I like your cam choice, but be prepared to spend some time on the tune. I would run a small double-pumper when on the street.