A fairly typical 1982p on the left. A fairly typical 1973D on the right. Note the crisp stairs of the 82. Note the weird bump on the stairs on the 73. Note the rim on the 82. Note how the rim of the 73 and the words United States of America have no crispness. I figure it takes about 1 out of 20 or more 73 to find a good example. Much closer to 1 in 5-8 of other years. What say yee?
Many factors can affect the appearance of both Cents.. Circulation wear, Worn Die Issues, design changes, Copper vs. Copper plated zinc planchets. What is your concern?
Copper plated cents are and have always been an issue from the start. This is why Zincolns will never stand the test of time. But also, if you are fortunate enough to find early examples or early strikes of older coins, before the dies show excessive wear , you are likely to find better examples still in circulation provided they have not been beat to death from use. It seems you are just having the bad luck of finding older coins that are more worn. Even coins in mint older sets were nothing worth writing home about and they were supposed to be better coins. Better coins are found in mint sets today overall because of better quality control, with the exception of Philly as are better business strikes found in circulation. I picked up early dated boxes of both P & D 2017 cents and they were already showing die deterioration problems.
Each date of cent has its unique characteristics. I consider the '79 far tougher than the '73 because it is usually heavily marked. It's true the '73 often has a weak strike especially on the steps but it comes extremely nice in the mint set quite often. I'm a huge fan of good strikes on moderns but the '73 cent has a good strike at least one time in twenty so isn't that tough. Look at the '72-D. This one comes Gem very commonly and with solid strikes from new dies. But I've never seen a '72-D with all the numerals in the date fully formed. A lot of the modern dates are overlooked because people have the mistaken notion that Gems are all common. The reality is that even nice BU's can be tough to find and Gems can be virtually non-existent. Try finding an '84-(P) with nice surfaces if you don't believe me. I'd guess they made fewer than 2000 Gems of this date and no more than a handful survive.
@cladking All so very true. And I recently saw a 1999 D cent that auctioned for over 4K. MS69 I believe, so it's worth it to keep eyes wide open, even with moderns.