Whose to say that these low market cap coins wont exceed where BitCoin is now (under 100 Billion) when BitCoin does reach the 1 Trillion dollar market cap?
BitCoin is a great coin, but it is not the only project being worked on in the blockchain world.
My strategy... Research research research, and do some more research, and when your at your REAL job, RESEARCH!!!
Find low market cap coins that have high potential. Check out their community, their developers, social media platforms, read all the content you can on their social media platforms, every tweet, every post on Bitcointalk from every member, who does what in a community.
Check out their project goals, read their whitepaper and their read map.
If your not spending hours on a coin researching it because it has none of that... Then it's a worthless coin. However some of these low market cap coins have very strong communities as well as goals in mind.
Just do all your research and make your best judgement on how much money you think you can lose on that project. Some projects are more worthy than others.