Vintage Schwinn

You should consult with your CPA as perhaps you need not be so concerned with trying to find a needle in a haystack with your search for the "greatest bike" on a severely limited & possibly unrealistic budget at this time given Covid pandemic's limited supply and still strong demand for specific bikes
Given that the new bike would be for business use, there may be factors that somewhat mitigate the somewhat higher cost for a better and probably more suitable bicycle.

Your need for speed as well as the need to outfit it with so much accessory equipment(......do ya remember the Beatles' Abbey Road album.....".ya gonna carry that weight, carry that weight, a long time..." ) The suggestion that others have made about considering an E-bike does certainly make practical sense.
Only you know exactly what your business might need from any particular bike or e-bike. My opinion is that when it is for something important for your business, you neither want to approach it foolishly or cheap-out with some second rate substitute solution. You also do not want to lose sight of what is most important. All flash and visual rarely works unless there is also solid practical functionality with that business vehicle too. For example, ABC Pest Control Company would likely be throwing money away if they opted to use a fleet of Escalades, or Hummers, or Lincoln pickups. It might be a cool promotional advertising gimmick if your pest control company is based in and serves Palm Beach, Florida, etc, . Ordinary millionaires and folks that probably earn less than 3 million dollars a year after taxes are likely more concerned that you are the best pest control service and still relatively competitive in total cost to your competitive peers. Certainly folks don't expect your pest control trucks to look like they have been past entrants in a demolition derby, but they all see that there is no common sense reason for their pest control's service truck to be luxury vehicles or something equally ridiculous. One does not need to be too bright to compute that "said hugely & significantly higher , fleet operations cost" will be passed along to the consumer as much as reasonably possible. Was it Johnny C. who said that if it don't compute, then you must dispute.

Ultimately, you should look at exactly what will be the most beneficial for your business at this time, and steer in that direction on the particular product that you should acquire. To rule out any seriously practical solution prematurely on either the basis of it being too costly or because you think it is uncool, is probably an immature short-sided viewpoint that will likely cost you much more in the long run. Everyone at one time or another experiences the "price of an education" because nobody comes close to getting a perfect batting average on business decisions and the choices that they make. Don't worry about that, but just make a concentrated focus on what is the most important one now for your business and try to select the best bicycle or e-bike currently available that can do that for you.