I will criticize SCVIV because these additions did make the game alot easier but like Egoraptor said, if you're going to change the player mechanics, you can't use the same level design, you'll need to add new level layout and new gameplay mechanics as well. That's what they should have done for RoB/DX. Keep the new mechanics, but add new challenges to keep the player on their feet. Make the player find good use of the sub-weapons and acknowledge their importance. Make the walls thicker so I don't kill the skeletons by whipping up through the wall rather than fighting them face to face. Change da game, not da playa!
This. Instead of abandoning this mechanic, Konami should have changed up the level design to force you to use the whip and sub-weapons in new ways. In other words, instead of having levels that are straight forward where you just had to get to the end and defeat the boss, design the levels to force strategic use of your arsenal to navigate and survive. Imagine how great classicvania would have become if with every new game built upon what was new in previous games.
For example, if CV4 had 8 directional whipping, CV5 would have level design that required it and sub-weapons to navigate as well as simply survive. The game after that would build on that and in a number of years, especially with the development of 3D, the N64 and eventually PS2 titles would have been much more epic and maybe we would have gotten a PS3 title that wasn't LoS and used the original CV Mythos.
I think 8-directional whip was never used, because you need very talented designers to make it work properly and design levels, that still would be challenging. It's much easier to design levels when your character is heavily handicapped.
This is the problem. Instead of building one something with real potential, the company cheaped out and made something that was easier to create. What a cop out!!! This is what turns off the community of fans. It's not surprising that a lot of fans jumped ship to the metriodvanias when they came out. For all the sh*t metroidvanias most get for being SotN clones, at least each new game had a different combat system.
Subweapons were very useful in many situations in SCV4. And level design, especially in the last levels, was rather unforgivable. Overall game was still challenging, thanks to creative level design. In comparision ROB was rather mediocre in that aspect, while compencating for its approach with a lot of content.
And, I agree with Sumac. Those last levels of CV were unforgivable. You needed a lot of skill and sub weapons, when you had them, to beat each stage. That is what the future of Classicvania should have been.