What you are doing is a good strategy because you can take advantage of the market's situation and conditions to benefit you. Not many people can be as patient as you in waiting for the market to go back up because they can panic and sell it as quickly as possible. But be careful if you want to buy altcoins because the price of altcoins can drop deeper and make you have to hold on to the altcoin for a long time. But for altcoins that have the potential to go up high, it can still be recommended but still be careful because we don't know what will happen in the future.
Long term of not, ignoring the dip and market signal as a whole doesn't seem like a good strategy to me. Sure we all know how Bitcoin is for the long term and eventually climb back and hit a new ATH. Though, looking for the best possible price both in the short and long term to reduce the risk is more sensible.