Alright here we go. I was in LOCO from day 0, before it was even advertised in Alaplaya. And it's still my favorite online game of all times.
TUTORIAL - ONE OF THE MAIN THINGS YOU NEED TO CONCERN ABOUT... The tutorial for new players for when they first start playing this game. Most of us were so in love with it that we didn't consider the learning curve of LOCO to be that difficult. But for new players that know NOTHING about MOBAs with RTS, TPS and RPG elements, this game can be their demise. The tutorial in LOCO taught absolutely NOTHING. Mainly because the whole point of it was just to forecast what the gameplay in LOCO would be like, when it ended up not being even remotely near that. The tutorial and overall help new players will receive from the game itself is what you really need to pay attention to. If you aim to keep the old "low-level" demo-like map for 3v3...you need to actually implement it in a way that will help newbies learn the whole point of the game WITHOUT having them wide open for destruction right after leaving the low levels. The way that old map was designed was WAY too easy to deal with and too weak of a challenge for new players to face and not end up being vulnerable to pubstomps as they progress into becoming more competitive.
Balance - Character balance is next. We had Stella and Octavian who were literally unstoppable monsters. Stuff like 10 skills to choose from, knockback on melees, 3 character cards to choose from post-death ingame...all of this was perfectly fine and made LOCO as amazingly unique as it was. But the balance was broken. Either the damage outputs or the general character stats needed serious work back in LOCO. Even the fact that mages were good for early game and melees were for lategame carry was ok as long as it didn't render mages COMPLETELY useless endgame and melees ridiculously underpowered and abused early game...which it did. Something needs to be done about that.
Management - Please keep in mind that EXTREMELY poor management of the game from both the publishers AND the developers of LOCO were the reason it got destroyed. And never pull the Evolution stunt in the name of all you hold dear. Keep it in the old CB phase (gameplay-wise) and gradually update it from there. If you really plan on adding a roaming type of lobby, just as long as you keep the old CB-styled gameplay it may even be fine. New characters shouldn't be the main focus of the updates. It should be game balance first and foremost, there's a lot to work with. If you're not 1000% sure what you plan with this game and how to fix whatever Danal and Alaplaya couldn't...better not get our hopes up too high just to crush them again. Kindly have in mind everything needed to bring out the full potential of LOCO out in the open and make it one of the best games ever. It sure could've been if the pubs/devs didn't fail at it miserably. By the way highly stable servers would also be a high requirement.
English - By the way it would be amazing if you could bring some good translators from Russian to English to the table. Unless you plan on keeping this game focused on the Russian playerbase, which would be bad, please consider doing a good and proper amount of work on the English version of the game. I don't know how you plan to advertise this game to the non-Russian playerbase, but looking forward to see how this goes.
You're gonna need a LOT of luck, so here's me wishing it to you. This could become amazing...but also fail miserably just like LOCO, keep that in mind. I'll see if there's anything I missed that I could add to the thread, but this is it for now.