Those are definitely your main options.

With the difficulty going up, option 1 becomes more and more expensive (on top of power consumption etc)
Option 2 is good in the medium term, with the company absorbing power costs, and with reinvestment your money goes a little further.
Option 3 is a good one in my opinion, as it is essentially the same as buying shares in a company. You will get paid if the company performs, so your pay will be independent of the difficulty of mining bitcoin.