First things first. You said the heads are 94 cc's but also that they've been milled. Have the chambers actually been measured since they were milled or are you just using the factory 94 cc spec? It matters. A lot. Milling the heads reduces the chamber volume and raises compression.
You also said the block has been decked - I assume you mean zero decked so that the pistons at TDC are dead even with the top of the block?
Which pistons are you using, and how much volume is in the valve reliefs and/or dishes (if present)? Lastly, what are the specs on your head gaskets (bore size and compressed thickness)? Without knowing all these measurements it is impossible to know how much compression you're actually running.
Cam - unless you've got enough compression, gear, and cylinder head air flow to support it, that Ram Air IV profile is definitely going to be a dog a low rpm. The Rhoads will help "some" but personally I'm not a big fan of them. They work by bleeding down lift and duration at low RPM, but in doing that they also introduce some 'slop' in the valve train and delay the lifter from moving until it's already getting onto the steeper part of the cam lobe. All of that adds 'hammering' to parts that can accelerate wear and cause problems. My opinion only - your mileage may vary, etc. However, if your compression is already "too high" then that big cam may actually be saving your engine by helping to keep it out of detonation. I wouldn't go changing cams to a much shorter duration (like that Voodoo) without first being sure of where you're at, compression-wise.
Valve springs. Assuming that they're 'right' for the cam you have now, switching to a cam that needs less spring pressure is always safe (mostly - it won't kill your engine but the higher than required spring pressure will tend to wear parts more quickly than springs that are "heavy enough but not too heavy). What's not safe is running springs that aren't heavy enough. If lifters aren't kept fully controlled and are allowed to be 'thrown' off the cam lobes, engine death follows very quickly.
Pushrods. Again, assuming the ones you have are the right length, a cam change won't alter that UNLESS the new cam has a significantly different base circle diameter and/or is a huge change in lift. A smaller base circle will tend to pull the rocker arm contact point on the valve stem "higher" (towards the intake ports) and a big change in lift affects how 'wide' the contact patch is - the more lift, the more rocker arm travel, and the wider the contact patch will tend to be.
Rocker arms - you didn't mention which rocker arms and ratio you're running now, and are you planning to change them?
Lifters. Are you planning to keep the Rhoads or will you be changing those also?