Well, I’m going to go on a different boat than the opinions below.
Now, don’t get me wrong; I love Pathfinder and 3.5. In fact, 3.5 is still close to my heart as it was the edition I played for years upon years. The Customization is great, the diversity of builds was wonderful, the simplified 3.5 (Pathfinder) made DMing much easier than I would have ever thought of it being…
Yet, I’ve come to hate it a little BECAUSE of the Optimization. See, I hate Power Gamers/Munchkins/Super Min-Maxers. These people have been the bane of my existence in Role Playing games. Why? Because, for me (Most games I’ve run and most gams I’ve played) were Roleplay/story based, not combat or extensive puzzle solving (I would say it was 75% Roleplay/Story and 25% Combat/Problem solving.) I feel that those who just try to be the best at what they do, becoming unrealistically good at what they do and just fail at everything else just irks me. Is it a wrong play style? No. But it is a playstyle I do not enjoy playing WITH. This is personal experiences, mind you. I am often referred to “The One who doesn’t play THAT KIND of cleric (The ultimate healer, the Controller, the buffer, the debuffer, etc.”. I like making things fit to the character, not to makes the character THE BEST at what he does while he lacks everywhere else. It’s just how I roll.
What does this mean? Well, let me show you differences between 3.5/Pathfinder and 5th Edition:
Armor Class: Gone are the days of 30+ Armor Class by stacking feats, magical items, spells and all of the above. 5th edition has changed this for the best. Most Armor classes now don’t go beyond 23-25, which means it’s always possible to hit something, but it also means the players are vulnerable. Just having an Armor Class of 20 is pretty powerful, even in the later levels.
Base Attack Bonus / Proficiency Bonus: Base Attack Bonus was something I’ve actually enjoyed, making the martial classes feel like they could hit everything well the levels went up, along with making the spellcasters (Which usually had lower Base attack bonus) feel like they were meant to be combatants. But, as always, here comes the stacking of 3.5/Pathfinder. Feats, magical items, special abilities, etc. came to add so many bonuses to attack that it was unreal at times (Low Level characters Optimized to hit literally anything, having insane bonuses could a lot of things stack.) 5th edition has Proficiency bonus (Which is equal all around for classes, only varying by what level you are) Made is so whatever you are proficient with, you get the bonus: Mages get it to their Spells and a few weapons, Thieves get it to many skills, attack and tools that they use (And are further improved by class abilities), Martial Classes get it to all the weapons available to them. All in all, made it relatively more balanced.
Concentration: Believe it or not, I think this was a great addition of 5th edition. Why? Again, the power gaming/absolutely overpowered characters that were the Spellcasting classes. No longer will you have a Bull Strength, Haste, Hold Person, Dominate all happening from the same person. Now, the choices of what spells you use are harder and you actually need to think through what concentration spell needs to be up at what time. Plus, for myself, fluff wise, it makes sense to be able to hold only one concentration spell at a time.
Skills: THIS IS ONE OF THE THINGS THAT REALLY DID BOTHER ME IN 5TH EDITION, BUT ALSO APPRECIATE AT THE SAME TIME. Again, gone are the days of having +15 (sometimes) to something at level 4-5 (Trust me, I know, I play Investigator in Pathfinder, go figure). 5th edition has it go up by level, and only those you are proficient in go up, no spreading points. I have to say, at first, that really, really bothered me, as I liked to have a diversity of skills sets to choose from. But, I’ve learned to appreciate the simplicity of it, since a lot of the skills uncompensated a lot.
^ These are the bigger things for me, but there are many other things I could comment on (Both for Pathfinder/3.5 and 5th edition)
Now, am I saying that you shouldn’t play Pathfinder/3.5? Absolutely not. I’ve come to see the balance between the two. Which one I DM will depend on the group I am with, the players I play with. As for which one I play, well, the DM is the one to decide. I think the only edition I would never return to would be 4th Edition, as I just don’t like how everything played out.
Though, I the end, I do prefer 5th edition for its simplicity without completely removing options (I know that character diversity isn’t as wide spread at before).