Before we caught on to how important is it to pitch enough yeast and control fermentation temperature, we were making really inconsistent beer. But for our last two batches, not only did we make 1 liter starters, but we also used a fermentation chamber. The first batch, a stout, fermented out really clean, and the second batch (an IPA) got going less than 7 hours after we pitched.
In both cases, we used WLP001 and set the fermentation chamber temp at 64 degrees. We have an old fridge that we've fitted with a Johnson Controls thermostat. For the stout, we made a starter without a stir plate, agitating it by hand as much as we could. With the IPA we used a stir plate, and got much better results when it came to growing yeast cells.
If you can buy an old fridge and set it up in a garage or basement (I think I've seen some on Craigslist for as cheap at $50), invest in a plug in thermostat (about $75), and use a stir plate for your starters (about $45), I feel the quality of your beer will greatly improve.
We've definitely learned through trial and error that two of the most-important keys to making great beer is pitching enough yeast, and then controlling fermentation temp.