I have played this game for a while and had some free time so I hope to teach you a few things. Just looking at this screen gives me quite a few recommendations. Don't take this as ragging on you. This is all useful stuff that I didn't know when I first started playing. The first unrelated thing I MUST add is that you need a poison healer. PERIOD. as soon as you get the curse "scavengers spawn periodically", you'll soon find you whole team getting 2000 poison stacks if they are not careful (that ended my first long run). that why you need a dedicated monster to deal with poison. I recommend the most broken support healer in the game, hydrim.
So from the top. Tizik should be in the middle so energize hits as many enemies as possible (3 instead of 2), Skimander is the best damage dealer to pair with tizik. At max speed, skimanders passive adaptability lets it deal 2500% more damage letting it easily cross the 10k damage per hit threshold with tactician 3 (I'm glad you have that keep it up!). Chikia is very niche. Im not a great believer in pack leader or outmanuever and the only real value I see in it is from fleet which reduces the swap cool down by 8 seconds which is insane when paired with a Mon who wants to switch most notably chip but other than that it scales quite poorly. Next there is a better way to use urso. its not meant to be used as a damage dealer or tank. its meant to make all of your allies attack instantly. Throw on a bunch of spyglasses and energy banners to get all your mana back instantly and get gang up and watch 4 of your mons attack instantly forever. tuskal is the most niche mon in the whole game. its good on 1 singular team comp which makes it arguably the most broken Mon in the entire game (get 1000 food per battle) but that's really neither here nor there. its the squishiest Mon in the game, it quickly stops doing meaningful damage and is hard carried by its revenge ability. Seras is good late game because you can get a lot of poison stacks. it actually hurt pairing it with unravelling prism because prism removes all the poison stacks that seras puts on the enemies! also pairing seras' cast with a giants short sword is very important for it to be relevant late game because debilitating bite has amazing side effects and already hits 3 times before short sword!. don't use radiant tome on it. I know first hand how appealing the healing is but in practice its not great. just go giants short sword and the utility double debilitating bites provides will be worth it I promise. As you play more you will find more synergizes and more mons that are broken in niche teams and thats what I think is so fun about the game.
Now if you are wondering what does get my stamp of approval, I'll tell you. Anything uses the two most broken items in the whole game. Heavy Shackles and Spyglass. Shackles lets your whole team get Max str and def and 3000 HP in a few loops with bulky 3 being a broken synergy so get that. And Spyglass not only gives 100% armor pen making your attacks deal 1100% more damage to max def enemies, but also spyglass gives all allies mana when you cast, letting you create an infinite chain of insta casters. I got to loop 60 using a broken team with amazing synergy and had to use cheats to end the run because I was tired of it. And the 3rd run I ever tried, I used heavy shackles (didn't know about spyglass yet) and got loop 15 before I died to (you guessed it) 2000 poison stacks! sorry I wrote an essay I hope this helps. if you read this whole thing you're a trooper.