Not sure if it's in our booklist or not but I just finished
Amazon.com: Can I Retire? How Much Money You Need to Retire and How to Manage Your Retirement Savings, Explained in 100 Pages or Less eBook: Mike Piper: Books . A lot of sound info that I really agree with. It was a freebie Kindle download a month or two ago.
I'm in the camp for VTSMX over individual stocks, and going ahead with investing a monthly sum now. VTSMX is pretty tax efficient and dividends at 15% aren't such a bad thing. I'm not a market timer so I believe in keeping my money invested and investing new money immediately. I've seen too many times when the good times kept rolling and I'd have missed out on upswings waiting for a dip to buy in on. However, if you decide you'd rather try to buy in only at more opportune times, that's your business.
I've gone both ways when I had ESPP shares. The thing is, you're already reliant on the company for your job, plus the stock options, so keeping ESPP shares really put you at risk if the company does fall on hard times. Continue staying enrolled in the ESPP, but consider selling as soon as you get them for the quick 15% (maybe more, depending on how they are set up and if the stock went up during the holding period) return. I rode my company's stock to FI, then lost over half of my net worth when it tanked. And this was also a solid Fortune 100 company. Diversification is a good thing. Hold it if you like, but understand the risks you are taking.
I wouldn't advise a second job unless it's something you'd really like to do. Some might like bartending, for example, or maybe you can do some independent contracting as long as it doesn't conflict with your primary employer. However, you might find that focusing on doing well at one job will get you promotions, bonuses, and more stock options and increase your wealth more easily than a second job will. Plus you'll probably maintain your sanity and not burn out.