“Start-up time” required: Poor – Experienced niche site builders will be well versed with outsourcing certain tasks and running through the whole process very efficiently, but when you first start out, it can take a long time to earn your first dollar from a niche site.  Doing research, designing the site, writing content, and doing proper SEO work can all be very time consuming, and the payoff isn’t always something you can rely on.
Under British rule, India's share of the world economy declined from 24.4% in 1700 down to 4.2% in 1950. India's GDP (PPP) per capita was stagnant during the Mughal Empire and began to decline prior to the onset of British rule.[103] India's share of global industrial output declined from 25% in 1750 down to 2% in 1900.[78] At the same time, the United Kingdom's share of the world economy rose from 2.9% in 1700 up to 9% in 1870. The British East India Company, following their conquest of Bengal in 1757, had forced open the large Indian market to British goods, which could be sold in India without tariffs or duties, compared to local Indian producers who were heavily taxed, while in Britain protectionist policies such as bans and high tariffs were implemented to restrict Indian textiles from being sold there, whereas raw cotton was imported from India without tariffs to British factories which manufactured textiles from Indian cotton and sold them back to the Indian market. British economic policies gave them a monopoly over India's large market and cotton resources.[104][105][106] India served as both a significant supplier of raw goods to British manufacturers and a large captive market for British manufactured goods.[107]
After employment, I think that most individuals gain income diversification through investing.  It is important to look at why we invest: because at some point we plan on using this money for something.  For most, it is saving for retirement, and the investing is done through vehicles, such as a 401(k) or IRA.  But investing is not just about stashing money away for a rainy day – that is what an emergency fund is for.  Investing is about having enough capital to generate income.
Whether you take a “distribution” (aka free-cash-flow) in the form of a dividend, interest payment, capital gain, maturing ladder of a CD, etc, you are still taking the same amount of cash out of your portfolio. Don’t fall for the trap of sub optimizing your overall portfolio’s performance because your chasing some unimportant trait called “income”.
Investing in bonds: Similarly, bonds are an attractive way to engage in passive income. Over a recent 45-year period, bonds funds, as measured by Vanguard Funds, returned 7.1%. Of course, there's no guarantee that investments in stocks or bonds will always work out well, investing in them is by far the surest way to generate money through passive income.
Secondly – and this is just quibbling – I’d change that risk score. The risk of private equity is incredibly high and should be considerably riskier than bonds! You are providing a typically very large amount of capital to one business that you agree to have no control over, and the success or failure of that business over a locked, predefined term determines your return. And in the few deals I’ve negotiated for clients, my experience has been that there are often management fees, performance fees, etc. that may cut into your potential gains, anyway. You’re putting a lot of eggs in one basket, and promising an omelet or two to the management no matter what. You really need to be confident that you found the next Uber before you take this giant risk!
I would throw in some caution here: if your spouse works at the same company, or in the same industry as you, you are not diversified, and should something happen, you could be in a world of hurt.  Companies do go out of business, companies do lay employees off.  There is nothing wrong with working together, but realize that you are not diversified and you should be trying to maximize other income streams as a result.
India is ranked 100th out of 190 countries in the World Bank's 2018 ease of doing business index, up 30 points from the last year's 130. This is first time in history where India got into the top 100 rank. In terms of dealing with construction permits and enforcing contracts, it is ranked among the 10 worst in the world, while it has a relatively favourable ranking when it comes to protecting minority investors or getting credit.[18] The strong efforts taken by the Department of Industrial Policy and Promotion (DIPP) to boost ease of doing business rankings at the state level is said to impact the overall rankings of India.[147]
In focusing on your wealth management goals, investment income is obviously critical but you might fund your goals from wider sources of income.  A typical long-term portfolio might produce about half its return as income and the other half as capital growth, though in times of duress the capital growth component wanes.  In this low-interest rate climate, some sources of income have become quite expensive and may prove disappointing against your spending needs.  But by tax efficiently and sustainably drawing income from wider sources, you might meet your goals while more prudently balancing risk against reward.