Yeah, the thing that surprised me out of all of this was how much I loved Lost Planet 3. I'll try and explain why to the best of my ability (I apologise in advance as I'm not a good writer)
Anyway the big thing for Lost Planet 3 is that it takes a much more storytelling approach at its core. The main writer of LP3 being the same guy who wrote the underrated Anachronox was especially surprisingly, a very dialogue heavy RPG with great writing. This straight away makes it very different from any of the others in the series. Lost Planet 1 and 2 are all about the action, they both tell stories but they are action games that want you in the action as soon as possible.
The big thing that jumps out with Lost Planet 3 is how different it is in pace, it's veeeeeeeeery slow to get into its story, as in surprisingly so. It's overall a very low key game and I can completely see why some folk just found it boring. When you first start the game you are new on the planet and have just started your job. You are a guy looking to earn some payola to send back to your wife and kid back home. The game starts off introducing the character Jim, and hence the player, to the world via basically doing Jims job. Planting energy posts, helping out other members of your team etc. You are essentially doing mundane things to start the game off with and dealing with the local Akrids is just another part of the job. Even Bills RIG ties into the story. With LP1 and 2 they are purely a gameplay mechanic, completely disposable and there to used, destroyed and another one grabbed from somewhere else. In LP3 it has a history, Jim built his RIG himself and it's a very clunky, slow machine made especially for contruction/engineering which Jim himself needs for his job. None of the upgrades for it are completely over the top, you don't all of a sudden get a chain gun, and it fits within the world they have built.
None of this would mean shit if it had terrible writing and voice performances but thankfully I thought the game excelled here. One big component of the game is that you get messages/and send messages back home to your wife. This would be soooooo easy to fuck up, like REALLY easy to mess up. But they didn't. I came to really like Jim and I felt the relationship between him and wife was genuinely touching and even realistic to an extent. I came to really like Jim the further the game went on and that drew me in and made me want to play more. I found none of the cast to be incredibly cliche an/or badly done. Their is one guy with a french accent who could have been so badly handled but thankfully wasn't.
Now from a gameplay perspective it's also different from Lost Planet 1 and 2, both inside and outside the RIG. LP1 and 2 as you have said have much more weight to them. They feel different to play. I enjoyed Lost Planet 3s on foot combat and it's fun but it doesn't really standout from any other third person shooter. It's much lighter than 1 and 2's combat and you can't just use your grapple anywhere, I was admittedly disappointed with this and did feel it was a bit of a step back. The number of weapons seemed pretty limited as well - shotgun, pistol, assault rifle, explosives. Nothing out of the ordinary really. The weapons feel good to use and sound great too, especially the shotgun which I used for a lot of the game so it's not a horrible game to play at all. But it's safe to say that it could have done with a bigger variety/arsenal of weapons.
The biggest change with LP3 is the RIG. As I've said you only have one RIG which you upgrade throughout the whole game and you control this from a first person perspective. The combat is from a first person as well and it's very slow and weighty. You have no guns and it's all about hitting Akrids across the head, grabbing their arms with your rig, squashing them etc. A fight with just a couple of them can get intense at times, at least when you're new to them and not sure how to take them on. The RIG is VERY slow and doesn't move fast at all (though you unlock fast travel later on in the game), they basically stay very dedicated to how limited/slow this RIG is. I also love the little touches such as the music in Bills cab. Your wife sends you music tapes which you can play and later on when it unlocks you can even play your own music. Something most people wouldn't even give a shit about but fighting an Akrid with 'We Fight For Love' from Commando blasting in the background is a very unique experience
I also found it to be an incredibly atmospheric game as well, I've read it described as almost Aliens like and I can see that. It's a very hostile planet, it FEELS hostile. The glistening ice, the atmosphere storms when you are walking outside in your rig and the crunching and breaking of ice all really drum this home. The game is set before LP1 and 2 and it feels like it. It's not a friendly place at all to be in.
It's not perfect of course. It has its flaws. It could have done with more weapon variety, the grapple not being able to shoot anywhere was disappointing and sometimes, during a few boss fights, it didn't really feel as polished as it should have. A bit more Akrid variety would have been nice and you can find yourself fighting the same enemies a bit too frequently. Multiplayer on PC also uses Gamespy which blows my mind. Awful, awful decision.
But yeah LP3 is so different I completely understand why fans of LP1 and 2 would especially hate it. I just think that overall it's a very underrated game and despite being from Spark Unlimited they did a great job, had a particular vision for their game and stuck with it. So yeah I guess I did like it a lot
However I firmly blame Capcom for the death of franchise over anyone else.