I feel as though Sonic 2 has bad level design but it is fun when you know what to do, WHEN YOU KNOW WHAT TO DO. Sonic 1 had intricate level design that teaches you how to play the game. Sonic 2 does not you can only figure it out through experience which would be fine if there was a save feature.
IMO Sonic 2 is more approachable than 1. Sonic 1 does give you Green Hill Zone to catch the basics, but 1 as a whole is more unforgiving. Examples:
- A glitch that Yuji Naka overlooked gives you an instant kill on spikes in 1. This sucks when you're in Green Hill Zone. And Marble Zone. Regardless of how you fall on them, you're dead. There's no chances to get up. 2 fixes this, save for the infamous pit in Mystic Cave zone 2.
- You can only earn lives through 1 ups or life boxes. 2 added the ability to earn one every 50k points, which helps the difficulty tremendously and helps to remedy the issue of 2 being longer.
- Special stages are few and far in between in 1, meaning that you have to get and keep 50 rings throughout levels. It's easy if you've played it several times, but when you're starting out its a very hard task to do. 2 gives you multiple chances and can happen at every star post.
- On that note, in 1 you only have 10 chances to get emeralds. In 2 you can get one in every stage save for Sky Chase and Death Egg, putting the count to at least 12.
- Getting continues is much easier in 2 because the special stages are designed with more accessibility to rings. 1 also gives you this chance, but with the way the stages control, it's much harder and Sonic's movement is too fluid to guarantee getting continues most of the time. Both games also let you get continues at the end of stages, but it's much easier to accomplish this in 2.
I think Sonic 2 is only popular due to people and their nostalgia and don't get me wrong i like sonic 2 for what it is but i just think it is grossly over rated.
The case here is the same case why people love Mega Man 2 over 1. For most people, 1 is much harder than 2. Naka and co. refined the code from 1 to have more content, more refined controls, and introduced a lot of the staples that are recurring in the series - the Death Egg, Super Sonic, and the Spin Dash are the most notable examples.
But people still hate it because they personally don't like but Sonic 2 on the other hand is a classic and therefore it can do no wrong? I don't think that's right and i feel people prefer 2 over one because 1 had pacing issues creating the illusion that it is less fun. But people just don't bother to really disect the games to see them for what they realy are.
Most people don't really break down why they like what they like in games. They either just follow popular opinion or they can't put into words what they like about them.
I can't say I've ever seen hate for 1. I've seen people hate either 2, 3, or 3 S&K because those titles are more noticed. Putting more of my opinion out there, 1 is probably the weakest out of the originals, not because it's a bad game, but because it was a blueprint for what put the other games on a spring board and launched them forward. 1 is very cut and dry, much like Super Mario. You have Eggman capturing animals and you rescue them. The others started the "Death Egg saga" and is where the game's story really got its roots. It also has a higher difficulty level too, which puts a lot of people off from classic games these days. Even as a kid though, I found 1 to be the hardest to approach and beat.
You don't sound like an angsty teen, and I hope I didn't come off as saying your opinion is wrong. That's not the case at all. While 2 is my favorite game, I've played the old Sonic games more than any old game from that time period and each one has their own strengths and merits.
I have to say it's refreshing to see someone prefer 1 over the others. That's pretty cool.