About to play as laguna. Anything besides the explosive order I should not miss?
Weapons, items, etc?
Actually is there something like an ultimate weapon or summon or something that i could possibly miss at start of game?
Hi, Naar! As others have said, make sure to attempt to draw on new enemies to see if there's a spell you don't have (you'll see ????) or that you want more of and to get the GFs from bosses.
You absolutely can just auto junction and what I usually do is auto junction to ATK and then when you've come across useful spells that would cause detrimental affects like blind or death, you can make sure that's what you have assigned to the status affect junction. If you are custom placing junctions, you can panel over to the left a couple times for status affect junctions and elemental junctions for both offense and defense. The game will put the most powerful spells on for you automatically or a balance of a spell that's strong and that you have the most draws of but if you think there's a more useful status affect you can change it or if you're fighting a boss with a particular elemental weakness, you can assign that. Note that you need to unlock status-j and elem-j passives from GFs in order to junction magic to status and elements. If your characters has a particular junction greyed out, they don't have a GF equipped that's learned that passive or you haven't finished learning the passive yet. You can spread your GFs around to make sure all three party members get all the junctions or most of their passives.
For the Laguna segment, there's also a key that you can find and he'll drop through a hole in his pocket that will allow you to get it later in the game as Squall. It's not a big deal if you miss these, they allow you to get some decent items but nothing crazy. Look at a gamefaqs if you don't want to miss anything with that Laguna segment.
As for weapons, you will find "Weapons Monthly" issues that show more advanced models of your character's weapons and what mats you need. Not everyone is covered in every issue. When you have all the materials, you can go to a junk shop and have them upgrade it for you. You will also see the more advanced weapons show up at the junk shop if you have all the materials on hand even if you haven't found the magazine revealing the recipe. I strongly recommend trying to get Squall's best weapon, Lion Heart before the end of the game, at least before the final dungeon. There are guides you can look up on how to get the ingredients early. There's even a way to get in on disc 1 if you play a lot of Triple Triad and various other grinding. That's for enthusiasts haha but it will give Squall a limit burst called Lion Heart that will obliterate enemies and bosses when you get Squall's ATK up. The reason I recommend it before the final dungeon without spoiling any story is that there will be a boss encounter that doesn't allow you to use GFs so if you've been using GFs all game you'll need another strategy to take that boss down and Lion Heart is by far the easiest method plus I think it's pretty bad ass particularly when you get Squall's ATK high enough to make every hit do 9999 damage haha I'd recommend waiting until Disc 3 to get it as there's a really easy way to get the most painful material so you don't have to play a ton of Triple Triad for it though I personally find Triple Triad to be the greatest mini-game ever and spend hours on it every time I replay the game.
Aside from that, concerning limit bursts, don't forget concerning Rinoa to check Angelo's progress on learning a new ability. You'll need to manually change it to what you want to learn so after you've run around for a while, check it in the menu. You'll learn new abilities for Angelo to learn via the "Pet Pals" magazines you find and can buy from Pet Stores. Zell is the other character who's limit bursts are learned from magazines in his case, they are called "Combat King".
This game is really flexible in letting you play as you want to. Everyone says to not level since the enemies scale but I max my characters levels every single time I play and have no issues. What's more important is that you obtain strong magic to junction to your stats. If you stay low level and do this, you basically break the game which a lot of people enjoy. When you have the means to travel around the world quickly on Disc 3 (you'll know what I mean when you get to that moment), bring it up here and we can point you to two islands that have the strongest spells in the game so you can put Enc-None on and just run around drawing like crazy and bounce between the islands. You don't have to do this but it obviously will make you super powerful.
Otherwise, just enjoy the ride, there's some really great moments through out the game and some incredible set pieces to experience so I hope you stick with it! If you like Triple Triad, you can convert cards into super useful items and materials that will also allow you to get a leg up on the game. You can even further convert items into magic if you wanted. Once you grasp the systems, this game is one of the most flexible out there. Feel free to ask any other questions you have! Enjoy the game!