I know that the Grass-type is unsexy because of all its weaknesses, but it's my favorite type. I always start Grass. To celebrate, here's a Grass monotype team that, if I were a Gym Leader, I'd trot out.
Sceptile @ Liechi Berry
Adamant Nature, 252 EVs in Spd and Atk, 6 in Def
- Leaf Blade
- Rock Slide
- Crunch
- Screech
Exeggutor @ Heat Rock
Modest Nature, 252 EVs in SpAtk and SpDef, 6 in Def
- Sunny Day
- Solarbeam
- Psychic
- Sleep Powder
Shiftry @ Leftovers
Modest Nature, 252 EVs in SpAtk and Spd, 6 in SpDef
- Dark Pulse (I used Faint Attack in Gen III when all Dark attacks were still Special)
- Giga Drain
- Extrasensory
- Growth
Breloom @ Salac Berry
Adamant Nature, 252 EVs in Atk and Spd, 6 in SpDef
- Spore
- Focus Punch
- Leech Seed
- Headbutt
Torterra @ Leftovers
Impish Nature, 252 EVs in Atk and SpDef, 6 in Def
- Earthquake
- Wood Hammer
- Crunch
- Leech Seed
And last, but most certainly not least...
Venusaur @ Leftovers
Calm Nature, 252 EVs in HP and SpDef, 6 in Def
- Toxic
- Leech Seed
- Double Team
- Magical Leaf
So... what do you think? I haven't assembled it yet, but it's a team I've been kicking around.