The most important % of the landscape business is getting clients. Keep in mind that you'll need to schedule a huge amount of time gathering new business. Anything less and you may hurt financially. You will reach a point (sooner than later) where you're so busy servicing clients that you won't have time or energy to gather new clients. Hopefully you'll reach that point and be charging enough (low balling = business death) to hire a crew leader so you can prospect more and grow your business.
I've found a 3 man crew is the most efficient crew size. 2 persons and they get tired and slack off. 4 persons and over and it starts getting labor expensive unless they have a full day of large (profitable) clients.
Back to your question - it's HARD to get clients. There are a ton of LCO's out there and you'll have to be very consistant getting in front of the decision makers.
Bigger mowers will greatly increase productivity. Everything I do is geared for increasing productivity. Including highly tuned machines, high quality equipment, efficient service routes... all that reduces overhead and contributes to profitability. Cients however don't give a poop if your equipment is new or 100 yrs old, all they want is results! Regular season hours are regular for a reason... it's needed then.
As for prospecting, forget the girls and meet homeowners/property managers in person. Let them know that you're the business owner (everybody loves to know the owner of a business) and you're willing to go that extra distance for them, fairly priced. Be persistant and contact frequently without being a nusiance.
Propsect, prospect, prospect and your business will grow. Low ball and you'll be working yourself to death and you WILL fail. Great service, fair price, good time management, consistant prospecting and you'll do well.