More coins are introduced everyday. There are numbers of low coins you can buy and hold now, your inability to do it now may also result to regret in 5years time.
If you think some coins are so expensive, buy the inexpensive ones.
These two sentences of yours are dangerous advice. You will also regret buying various coins expecting their value to shoot up when that never happens. Just because a coin is cheap now and it used to cost more in the past, that doesn't mean it will ever reach those old highs ever again. Check the records and look at the TOP 10 coins back in 2014/2015 and compare the names and the value with what we have today. You will find just a few survivors.
Bitcoin has shown time after time that when it prospers, so do other assets. To minimize your risk, stick with the familiar options and don't overdiversify.