@Ljiljana You pulled heroes using a x10 red elementals and was able to get Neith as a lucky draw, along with Gormek.
Gormek maxed will be useful as a viable tank due to his high health early on until when you get a better hero to serve as tank. You may also want to max Boldtusk to serve as tank in lieu of Gormek. Colen has high attack and may serve early on against titans and for stacking with your other red 4 star heroes. Among the 3, I suggest maxing either Gormek or Boldtusk first, depending on who you are making as tank, followed lastly by Colen. Do this only when you have 3-4 rainbow teams of maxed 3 star heroes, especially if you cannot ascend to the final tier BT or Gormek.
Among your 3 star fire heroes, maxing 3 Nashgars (unless you get 3-4 Namahages in Atlantis), 2 Jahangirs and Hawkmoon will be useful for 3 star raid tournaments, removing Hawkmoon if it is going to be a Bloody Battle where healing and reviving dead heroes are not available.
For your greens, Brienne and Berden (the latter is surpassed by Hisan from the Sand Event or by Mnesseus from Atlantis) are good for 3 star raid tourneys. Brienne increases the attack rate of all your heroes when her skill is activated. Kashhrek is a fine tank who has better defense and health than some of the 5 star heroes but his only purpose is to serve purely as tank as he his skills involve healing to himself and nearby allies, including elemental defense against red attacks. Melendor is a better healer as he heals all, has high attack (good for titans) and dispels enemy buffs but is squishy.
You cannot get wrong maxing Kiril as he is a walking Dragon Banner when kept alive and skill active.
Try feeding same colored heroes since it is food efficient. Level heroes of each element one at a time, pausing only if you lacked the ascension materials or stopping when they reached max level.