The market _should not_ be liquid. Liquidity is great, but you haven't provided any reason it's better that the market be liquid. Your first example (loaning you money) is credit markets, not stock. And credit markets become looser if stock markets become stricter, since stock is better collateral for loans, so here your example supports my scheme.
Credit hiccups would not go away in my scheme, but day to day sensitivity to credit markets would be reduced if executives were incentivized to look after long term stability of companies instead of quarterly profits. Do you believe Ford or Standard Oil, in their heyday, would have been crippled by being unable to get loans from WallStreet? If a company fails for inability to get a loan, they have been painting themselves into the corner with bad decisions for years.
Finally, why shouldn't the stock market be glacially slow? Stock prices could change just as quickly as they do now, since buy orders could be entered and removed instantly, just as now. The only thing this would prevent is people flipping stock as short term investments, and so stock _would not_ fluctuate as much, since there would be so many less trades overall. Short term investments are always (no exceptions) an attempt to game the system or trade on inside information, and there is certainly no way to profit in the short term except by fomenting, using inside information or trading far quicker than the average investor so you can respond to news more quickly. All of these activities hurt the efficiency of the market, so the market becomes more stable and prices more accurately signal company health than they do currently. When you have a stable market, price ratio's can increase since risk is reduced, and that is good for everyone when it is sustained.