Scaling alone doesn't make it an RPG. Every FPS with a difficulty setting has scaled attributes. Do you really think, after countless updates, and doing the math, TWI would still call it suicidal when it's as challenging to high level perks as normal?
I don't think so. If TWI wanted, they could make your Rank 6 awesomeness feel like Rank 0 on suicidal, today. Changing one integer could make clots soak an entire clip of AA12 rounds. They could move faster than you could type out a snappy reply. They could attack you at range with melee and kill a fully armored berzerker in one hit.
I find it really hard to believe that you only lose on suicidal because of other people Evilsod. I'm not attacking your skill...but all your exaggerated statements about the difficulty of suicidal are hard to swallow. Fact is, as you like to say frequently, people die A LOT and the game seems pretty damn hard for many, even before suicidal.
When the time comes, if need be, suicidal can be rescaled. Ranks vs difficulty used to look like this:
Rank 0: Beginner.
Rank 1-2: Normal.
Rank 3-4: Hard.
Rank 5: Suicidal.
Now, it looks like this:
Rank 0: Beginner.
Rank 1-2: Normal.
Rank 3-4: Hard.
Rank 5-6: Suicidal.
If we keep seeing the rise in weapon power of the last update, then yes, a difficulty tweak will be necessary. If we keep getting new weapons with every perk level, and they go all the way to 10, revising specimen HP along the way, it could look like this:
Rank 0: Beginner
Rank 1-4: Normal
Rank 5-8: Hard
Rank 9-10: Suicidal.
Or who knows? Maybe this is the relative peak of power that TWI will go to. Maybe from here on out, new weapons will vary in style and other aspects, but won't edge up damage very much. Same thing with perk bonuses.
Point is, there are a ton of unknowns in how this can play out. Scaled stats according to difficulty could be tweaked, guns may not get significantly more powerful in later updates, existing weapons could be rescaled, new specimen might get introduced, the make up of entire waves at different difficulty levels could be altered, and from the top down the game could be rescaled to accommodate higher level perks and weapons.