Most Texas Hold'em players start the same way. They open with almost anything and lose their shirt. Then they memorize open and call Range charts and do much better. With some playing experience they learn to adjust ranges based on opponent actions or reads. That is good. Then they stop using range charts and that is bad.
It would be better to start adding preflop ranges, like 3 bet, call 3 bet, all-in and call all-in. Then ranges for specific tactics such as Button squeeze, steal, isolate, min bet. Ranges for Small blind and Big Blind.
Modern poker is becoming more and more about frequencies. For most poker actions there is a best frequency. For example bluffing on the Flop. Minimum Defense Frequency ( MDF ) is a simple equation, pot / (pot + bet). With a half pot bet the mathematically correct frequency is 66.7%. Trying to estimate how you are to 66.7% that number while playing can be nearly impossible. But, if you use a MDF range you can get very close without doing any math in your head. Use a MDF Range chart, on
any street, and dramatically improve your win rate.
What many people misunderstand about ranges are that they are basically a simple way to effectively implement frequencies. Doing something x% of the time, while using the best hands, is far from easy to do. A range chart and be developed away from the table and memorized.
Ranges can be used for things like a C-Bet, float, barrel, or many other exploitative tactics. Yes, there is a best frequency for a C-Bet. A range chart can get you very close.
Your opponents also have a range. You can learn to estimate opponents ranges fairly closely. If your average opponent Middle Position Open range is 18%, and he opened preflop, then you can get very close to what cards are likely in his range. Compare your range and what hand or draw you have on the flop to your opponents range. This is a very valuable read.
All ranges, like your old preflop ranges, can be adjusted based on experience and your read on your opponents. That makes them more valuable, not less.