Ok, lemme say this. I Played LP1, LP Colonies (Which brought me back gaming and I loved it and the Multiplayer OMG! It was AWESOME!!!! I still play from time and time again). I  tried LP2 and I kind of enjoyed the campaign and I didn't get the whole ranking thing. But I finished the campaign. I give Capcom props for making the camp-PAIN Challenging :).
I didn't like the mulitplayer (which was the whole reason why I bought the game) I end up selling the game a week later. But I kept my copies of LP and LP Colonies.  Now we got LP3, I am enjoying the CAMP-PAIN and I have put in about 13 hours in and why did you put no guns on the mech??? A drill? A clamp? OMG! Just the thought of walking in the map drive me nuts! 
I tried the mulitplayer and I hate it! I kept glitching in the game and at one point I was on the ceiling of the cave and everybody was battling below me. Lucky I was smart by just renting the game this time on this one. But after I finished the CAMP Pain I am not playing it again. I am a huge LP FAN! I even want the LP Console! Why didn't you just add new maps to the old LP and LP Coloines? 
One thing with Call of Duty is they never make too many changes and just changed the weapons? Have you considered this?
It seems like you make too many changes and it is a completely different game.  I like the old style of arcade of LP and LP Colones. I like LP3 new graphics and the 3 person and the shoot and roll of the shot gun, especiall throwing gernades and shooting it. IT WAS FUN! OH YEAH WHAT HAPPEN TO THE TAUNTS?? I don't know your plans for LP4 but try to stay with one format maybe that would help your confusing your fans.