J C Lawrence
Is there ever a time when you might be able to float a company but should choose to delay it in order to affect other elements of the game?
Yes. It is a fairly common tactic.
Or should you always open a company as quickly as possible?
No. The choice of when and how to open a company is significant and not an automatic.
What would be some circumstances when you should delay? and what would be your goal in delaying?
The biggie is to first secure the desired presidency. After that there can be opportunities to manipulate the market, operating order, buy good shares etc -- putting their capital to work for them before committing it to the new company -- only finally floating the company later in the SR as convenient or when pushed/attacked.
Additionally a player may secure a presidency without floating the company. This is a fairly common mid-to-late game tactic. It is usually done when they could float it now if pushed/attacked, but would prefer to wait until the next SR (usually because they would have to sell more than they'd like to float it, or because they're waiting for more non-permanent trains to be bought). By securing the presidency the player need not care about the location of Priority in the next SR and can often gain a positional advantage despite having two shares of capital locked up in a non-producing company.