Characters with the Fly special rule (or mounted on a flying warbeast/monstrous beast) CAN join units. The exception being a character with the Arabyan Carpet. The only units Flying characters cannot join are Units with the Fly special rule, as no characters can join those units.
"If a unit is engaged to more than one facing (say to the front and one flank), it cannot make combat reforms." BRB p. 55 This rule is often missed in many YouTube battle reports that I watch.
Did you know that with a BSB Slann you can put both the Skavenpelt Banner and the Razor Standard in a unit of Temple Guard giving 3 attacks with -3 to armour saves. Wish someone had told me about that combo earlier.
Did you know that you can put a skink priest in a unit of skirmishers? I may be a total derpnoob, but I just found out about that one the other day.
Did you know that If a Slann Mage-Priest who knows Flaming Sword Of Ruin spell and successfully cast it upon himself, It is technically the Slann's skink attendant that physically bears the flaming sword?
Did you know, that when fighting against a unit consisting of a rank (or when a bigger unit get reduced to a single rank), you are supposed to remove casualties alternating from either side. It is situational but it is a great way to reduce attacks coming back at you. So although you have to maximize the number of fighting models you should still aim for corners with your charges. Especially with things like chariots and stegs (with impact hits), or units with high I. Just remember you can't lose contact this way. If you kill more models then are in b2b contact you are supposed to move one unit a little, but then you dont have to maximize anymore.
With Khaine magic, you can use the Engine of the Gods to lower the casting value of a 15+ spell to 14+ which lets you cast it multiple times.
a slann with lore master and life magic w/ 1 or 2 lvl 2 SP both beast magic minimum amount of core thats required to be legal, a trogladon w/DR and as much points as your willing to invest in to a TG bunker with chatax and you will find it hard to die (as long as your dice rolls are good) i done this in a 2.5k pt fight i had other stuff as well to fill points and different rolls but i can't remember of the top of my head all in all was one of my most enjoyable battles and my opponent was impressed with my tactic (up until this game i had only played 2/3 games of 8th and about 10 games of AoS) so as you can i had no real good army building experience at that point and this was my first good list.
Number 1 is great. Number 2 is... wrong... You have handler models that go with the monster, but you can place them behind and they cannot be separately attacked. Althought they CAN attack!
The ONLY thing about it is if you lose a combat, you lose the Frenzy which kind of sucks as it costs 65 points... There's no rule that says it is a special Frenzy so if they lose ONE combat, its gone.