Wow, you put a lot of thought into this. Quite complicated system you've come up with. Sounds like a good idea, but difficult to implement so much stuff. Are you a coder? Maybe you could implement it yourself if you know how to code...
Oh and you aren't entirely accurate about how to gain new property in the current version of the game. Currently, you can gain new property by:
1) Taking over a CCS property.
2) Taking over a Crack House.
3) Renting apartments (this is only temporary though).
You can set up business fronts at CCS properties and Crack Houses you take over, but not at apartments, at least currently.
Coincidentally with your interest in business fronts,
in revision 712 (which came out less than a day before your post), I increased the number of possible different business front names from 5 to 28. Before it was just 3 types of insurance and 2 types of temp agencies. Now there are 7 types of insurance, 7 types of temp agencies, 7 types of restaurants, and 7 miscellaneous business fronts (Real Estate, Imported Goods, Waste Disposal, Liquor Shop, Antiques, Repair Shop, and Pet Store). I tried to think of business fronts used by the mafia. So Italian restaurants are used by the mafia, sometimes the mafia say they are in the "Waste Management" business, sometimes they say they are in the "Import/Export" business. All 3 of those are covered among the 28 options now. 28 is an arbitrary number, it was hard to think of more than 7 types of insurance that had short enough names, and I felt it would work best if each of the 4 categories (insurance, temp agency, restaurant, and miscellaneous) had the same number of possibilities. It used to just be 2 categories, I added restaurant and miscellaneous.
Oh and your idea to INCREASE the number of available hideouts in each city would make the game too easy, there are already enough available hideouts in each city, no need to add any more abandoned buildings or places to rent, there's plenty already. (Have you tried taking over the Crack Houses or renting apartments? You aren't just limited to taking over CCS hideouts, you know.)
Still, most of what you propose IS a good idea (namely the new more complicated system for business fronts that you can actually work at, embezzle from, etc.) I don't quite see how a business would provide a liberal influence though (for instance, if you have a bunch of liberals running an insurance agency, how is that going to make anyone liberal, it's not like they are going to chant liberal slogans at all the customers is it?) I don't really see how you'd influence the political views of your customers (subliminal messages? no that's rubbish).
Also lots of businesses have trouble starting out, and in fact many large corporations have divisions that are unprofitable (for instance Microsoft only has one profitable division: the operating systems division, which makes HUGE profits off Windows... all other divisions of Microsoft, especially the gaming division that produces XBoxes, lose money, but Microsoft keeps those divisions operating anyway because they want to expand into as many things as possible just so they don't have all their eggs in one basket). If a business's total net worth is negative, but the Liberal Crime Squad itself has enough money, it ought to be able to pay the business's expenses. So they should really only go kaput if their expenses add up to more than the Liberal Crime Squad can afford, or if you decide to close them to stop losing money.
Oh, and each business would also need a minimum number of workers, you forgot to mention that bit. For instance, a restaurant can't just have 1 or 2 workers, that's ridiculous. If a business doesn't have the minimum number of workers than it can't be open to the public, it would have a "CLOSED" sign on the door (which would be locked), and not provide any bonuses.
Also, don't you think the idea of running businesses is a bit Conservative? The Business skill is highest in Corporate CEOs and Corporate Managers, who happen to always be Conservatives. The idea of Liberals putting a lot of time and energy into running a business is kind of... well... it goes against the political stereotypes of this game. Of course, one could argue that while large corporations are inherently Conservative, small businesses are perfectly capable of being Liberal. Anyway, maybe if your business gets too big and gets too many customers and expands too much, it could run the risk of turning into a Conservative corporation and backfiring on you somehow. Or maybe having it get big enough to be a corporation might actually be good, since you'd be able to keep the business Liberal and now you'd have a large corporation run by Elite Liberals rather than Arch-Conservatives. If we go even further with this (rather ridiculous) idea, if your business operations get big enough, the Liberal Crime Squad could become a Fortune 500 company and get listed on the New York Stock Exchange as "LCS" and have its stocks traded on Wall Street. Yes, that sounds quite ridiculous, having people buy and sell "Liberal Crime Squad" stocks on Wall Street. But it would be funny. By the way, did you know that stock symbols on the NYSE stock exchange are 3 letters or shorter, while stock symbols on the NASDAQ stock exchange are 4 letters or longer? Interesting factoid. That's how those 2 competing stock exchanges keep from having different companies have the same stock symbols (the NYSE and NASDAQ are competitors, each of them wants to dominate the stock-exchanging business and crush the other one like a little worm).
So just to reiterate, while I think most of your stuff is a good idea, I don't agree with all of it (namely increasing the number of locations the LCS can take over, and having business fronts influence public opinion in the liberal direction), and think that it needs the following 2 changes: 1) Business fronts would need a minimum number of workers to stay open. 2) Business fronts that are unprofitable would still stay open as long as the Liberal Crime Squad has enough funds to cover their expenses (although you'd get an option to shut down an unprofitable business if you don't want to keep losing money to it).
Plus it would be quite hard to implement such a huge amount of stuff like what you are proposing. Very ambitious goal there.
Anyway those are just my thoughts on this idea, I'm sure plenty of other people have thoughts on it as well.