Totodile is already in A and isn't moving. It was among one of the very first placed mons in this list. You can continue to test of course.Sorry for the double post, but I have test results! As I earlier mentioned, I began testing Totodile.
Level: 10 (11 after beating Pidgey)
Log: Spammed Rage x3 until Pidgey fell and x2 for Pidgeotto. No items necessary, ez ez.
Level: 16 (17 after beating Metapod)
Log: Rage spam once again. Metapod actually Tackles you pretty often (and Kakuna went for one Poison Sting at least on two runs) so building up Rage is pretty easy. Scyther caved to Rage x2, failing to do more than bring Totodile to the yellow with Quick Attack x2 or Fury Cutter x2. No items.
Rival 2: D (without Fury Cutter), C/D (with Fury Cutter)
Log: Pretty bad fight tbh, but winnable...only if you have Fury Cutter. Water Gun 2HKOes Gastly but Gastly and I speed-tied. Bayleef often tries to start with Poison Powder or Reflect and did so on two runs; however, Bayleef also OHKOed on me two runs with one critical Razor Leaf. I did beat Bayleef on one try by setting up Fury Cutter for three hits, thanks to them trying to start with Reflect, missing one Razor Leaf, and landing a non-crit one eventually; Zubat falls easily to 2-3 Water Guns. Healing support (Parlyz Heal) was necessary on 3rd try thanks to Lick.
Whitney: D (without Fury Cutter), B/C (with Fury Cutter)
Log: Surprisingly brutal fight tbh, and Rage spam failed me on three different tries; the damage accumulated from Clefairy, coupled with Miltank Rollout/Stomp, killed me each time. Things went better with Fury Cutter, but not by much - the first try went smoothly, but the second try Miltank flinched me and killed me with two Stomps after Clefairy already brought me to yellow. The third try, Clefairy killed me with Metronome -> Dragon Rage when I had less than 40 HP remaining and was setting up Fury Cutter. Fourth try (yes, a fourth), I won again with Fury Cutter spam; crazily enough, Croconaw amazingly kept going through a Metronome -> Thunder Wave AND a Stomp without paraflinch and critted Miltank with FC.
Rival 3: B
Level: 23 (24 after beating Magnemite).
Log: Haunter outpaced and Cursed Croconaw each time only to die to Surf; Magnemite got OHKOed, and Bayleef...is interesting. If Bayleef uses stuff like Poison Powder - which he also missed twice on my second try - Ice Punch can 3HKO reliably for the win as you can take a non-crit Razor Leaf (a crit kills you, however; and you want to switch to a teammate ASAP so you can dispel Curse and heal Croconaw). I lost on my first try due to Poison Powder, Curse, and Razor Leaf damage all accumulating though. Zubat dies to Ice Punch easily enough. Not bad, but needs some team/item support.
Morty: D (without Dig), B/C (with Dig)
Log: Failed in all three non-Dig tries; Curse, combined with the superior speed of the non-Gastly Ghosts (Gastly had a speed tie, my Croconaw has a bad Speed IV) and Shadow Ball/Mean Look/Hypnosis shenanigans killed me each time. Things improved after I taught Dig and equipped a Mint Berry for sleep. Surf 3HKOes Gengar, OHKOes Gastly, and 2HKOes both Haunters (and OHKO after Curse on 1st Haunter). Dig one-shots the first two Ghosts but not the final Haunter or Gengar, both of whom are 2HKOed (Gengar actually was 3HKOed at one point IIRC). Overall, winnable, but you need to cast aside a good TM move to improve your odds sufficiently. SE Bite is weaker than Surf and SE Dig btw.
Current verdict: Was really impressed by Totodile earlier in the game, but from the Rival onwards takes a serious hit. Their lack of speed, bulk, and power really start to show from Whitney onwards, causing them to be status bait and take damage more often while failing to KO fully evolved Mons or Mons with comparable bulk even with SE moves. Fortunately, I am only 5 levels away from Feraligatr and hope to reach it by Chuck!