When it comes to long-term holding and certain profit yield if one can be patient, Bitcoin undoubtedly remains number 1. No matter the market fluctuations, it will always rise up again and give profits as it always does. But when it comes to altcoins, it is safer to holding the top list of alts, as these has been tested, except one wants to make jokes with his/her funds by randomly having in possession numerous coins, with expectation of it skyrocketing in the near future. This most times do turn out well, but on rare cases.
As a business-oriented person, the goal is to make profit and minimize the risk/losses in every possible means, and when that comes to the crypto industry, it means putting above 60% of one's investment into Bitcoin, and diversity the rest, or still, put 90% and keep the remaining 10% for maintenance.