I think I will allow SS and SSS to be normal attributes and allow for legendary pokemon to have them normally.
Why? because moves that buff and debuff could be simulated by raising their letter grade.
Anyhow so... Here are the starting stats
F-: 1
F: 1
F+: 2
E-: 2
E: 3
E+: 3
D-: 4
D: 4
D+: 5
C-: 5
C: 6
C+: 6
B-: 7
B: 7
B+: 8
A-: 8
A: 9
A+: 9
S-: 10
S: 10
S+: 11
SS-: 11
SS: 12
sS+: 12
SSS-: 13
SSS: 13
SSS+: 14
Lets use that for starting stats...
So lets arrange this for the first 10 levels... or 50...
Now at the rate things increase basically... things get more frequent as you level up. I am going to assume the starting value is independent of stat increase... and that you don't get a stat increase first level... but level 2 and on you get a bonus points
x/x is level 10 and level 50
F- (0): 0/0/0/0/0/0/0/0/0/0 Total for level 10: 1
F (1): 0/0/0/0/0/0/0/0/0/1 (TOTAL 2/6)
F+ (2): 0/0/0/0/1/0/0/0/0/1 (Total: 4/12)
E- (3): 0/0/1/0/0/1/0/0/1/0 (Total: 5/17)
E (4): 0/1/0/0/1/0/1/0/1/0 (Total: 7/23)
E+ (5): 0/1/0/1/0/1/0/1/0 (Total: 8/28)
D- (6): 0/1/0/1/1/1/0/1/0 (Total: 10/34)
D (7): 0/1/0/1/1/1/0/1/1 (Total: 11/39)
D+ (
: 1/1/0/1/1/1/0/1/1/1 B1 (Total: 13/45)
C- (9): 1/1/1/1/0/1/1/1/1/1 B1 (Total 14/50)
C (10): 1/1/1/1/1/1/1/1/1/1 B1 (Total 16/56)
C+(11): 1/1/1/1/1/1/1/1/1/2 B1 (Total 17/61)
B- (12): 1/1/1/1/2/1/1/1/1/2 B1 (Total 19/67)
B (13): 1/2/1/1/2/1/1/2/1/1 B1 (Total 20/72)
B+ (14): 2/1/1/2/1/1/2/1/1/2 B2 (Total 22/78)
A- (15): 2/1/1/2/1/2/2/1/1/2 B2 (Total 23/83)
A (16): 2/1/2/2/1/2/2/1/1/2 B2 (Total 25/89)
A+ (17): 2/1/2/2/1/2/2/1/2/2 B2 (Total 26/92)
S- (18): 2/1/2/2/2/2/1/2/2/2 B2 (Total 28/98)
S (19): 2/2/2/2/1/2/2/2/2/2 B2 (Total 29/103)
S+ (20): 2/2/2/2/2/2/2/2/2/2 B2 (Total 31/109)
Ok well that was a lot of work...
I will try to think of moves... as they should have "tiers" of damage at least in conception...
I'll use 5 tiers... I remember how they work.
Fury Swipes is 1, Tackle is 2, Swift is Tier 3, Megapunch is Tier 4, and Hyperbeam is Tier 5.
Basically that the tiers kill you early on... but gradually let up a bit...
Also if anyone wants to comment or anything go ahead... though I admit there isn't a lot of say here...