You're just waffling without actually saying anything. You've not given any actual examples of why 2 SPWs with more varied missions wouldn't work other than "it's bad game design". It's not overcomplicating things, simply adding more variety.

Don't get me wrong, I love the AC formula, but there's no reason for your insistence that it has to be this way, other than "it's always been this way why fix something that ain't broken". The fact that you can't comprehend a level that can require two different special weapons, and also be fun, is very close minded of you.

I can tell you're a very stubborn person who isn't going to change their mind so I'm not going to bash you over the head with my opinion any more, but please consider that fact that games can change and evolve, and there's no reason why level design can't change to accommodate the simple addition of one extra weapon, it would not change the game as much as you think it would. You can already switch weapons almost immediately in missions with return lines, this would just remove the need for a pointless and immersion breaking retreat.