How about Smeargle? I don't know how Sketch works in PMD, but if you can Sketch your partners, then it should be easy.
+Heat Wave(Fire-type, hits all foes in the room), Silver Wind(Bug-type, hits all foes in the room), Spore(puts all foes in the room to sleep), anything.
+Group F in PMD2, which gets Multitalent which gives 5 extra PP for all moves. Also gets All-Terrain Hiker. Also gets Trap Buster(may destroy a trap when stepping on it). Also gets Stair Sensor.
+No 4x weakness.
+Body size 1.
-Average stats.
-In PMD2, isn't in Group D or G, so no Trap Seer(does not trigger traps).
-Single-typed, so only one gummi.
Stats aren't that big of a deal, since you can get and use stat boosters endlessly. Use some and the pokemon isn't weak anymore.
In case anyone is interested,
this shows the stats of all pokemons. It's a PMD1 guide, though, so it won't show any of the new pokemons, and some pokemons may have different stats in PMD1 and PMD2. I'm assuming they aren't.
How about Golduck?
+Great stats
+Group C in PMD2, which gets Nonsleeper, Erratic Player(increases multiplier of super-effective moves), Extra Striker(may attack twice), Intimidator(may make enemy cringe after an attack).
+Has Damp, which nullifies Selfdestruct and Explosion.
+Has Cloud Nine, which nullifies weather effects.
+No 4x weakness.
-In PMD2, isn't in Group D or G, so no Trap Seer. Isn't on Group A, D, F, G or J, so no Stairs Sensor. Not suitable for leader.
-In PMD1, if not obtained as starter can only be obtained late in the game in Joyous Tower.
-Single-typed, so only one gummi.
;006;
Charizard
Pros
*Heatwave. {Monster House fail to be a pain now...}
*Dual type. {IQ can be rasied super fast.}
*Excellent Stats. {Nuff said}
*Superb lvl 1 Stats and Moves. {Dragon Claw, Heat wave...}
According to the guide I mentioned, Charizard's level 1 stats are lower than a Geodude's.
And in PMD1 Heat Wave is a level 0 move(so you can use it in level 1 dungeons, yes), but in PMD 2 it's a level 59 move.
Kecleon. Best stats ever.
His stats are good. Just good, there are lots of others with better stats. They just say Kecleons are very strong because they're at level 90.
Level 100 Smeargle:
158 HP, 88 Atk, 52 Def, 92 Sp.Atk, 51 Sp.Def
Level 100 Kecleon:
205 HP, 103 Atk, 77 Def, 103 Sp.Atk, 71 Sp.Def
Level 100 Golduck:
229 HP, 139 Atk, 89 Def, 147 Sp.Atk, 89 Sp.Def