The Devs already have this in the shop, several version in fact - the Fast Lane Pack is my favorite - so I don’t see them adding it.
My wealthier friends say most challenge event summons, calendar summons, and Atlantis summons keep them over supplied with 3* heroes considering the hero roster slots you have.
Except for skill rolls traps ( off color trainer heroes, same color trainer heroes and off color 3* heroes ) much of leveling is designed to be irrelevant and grindy.
Pokémon GO has an interesting mechanic. ANY Gacha based summons in the game has a chance of being any tier and any level.
So in Empires your newly summoned 5* Joon would have a 1 in 260 chance of being tier 4, level 80 ( actually they cap it around 5* 4.40, must sell those fast lane packs, so 1 in 220 and this is usually during special events, depending on the local weather boost- another way to increase spending without actually giving the player a huge RNG boost-, so more like 1 in 1000 the rest of the time. But still a 1 in 1000 ).
I actually got the equivalent of a 4* 4.05 Wu Kong Gacha summons last week ( pinap, double candy, Tyranitar, in the wild, at the end of my street for the win ).
This would be cool for cash players because 3* 3.25 are worth more XP than 3* 1.1 when leveling another hero.
Imagine the joy on a newbie’s face when his first summons is a 3* 3.25 Bane.
It seems over powered and a bad business plan until you realize the number of 3* 3.25 Carvers summoned vastly outweighs the number of 5* 4.40 Joon.
But just like Poweball jack pots ( though it it actually based on the current scratch off ticket business model), the thought of an elusive 5* 4.40 Joon summons increases spending, since each is Gacha summons is different cash players actually don’t mind 3 HotM summons in a row, the dribble of 3* 3.25 Carvers makes each 3* summons less boring, players actually groan when getting a 5* 1.1 Joon or 3* 1.1 Carver ( with much teasing from their teammates), it doesn’t replace trainer heroes fast lane pack’s superior XP award.
This actually gets min/ max players to use some of their Guardian Owl, Thorne & Guardian Kong for better data mining and rebalance data. So you cannot make it just 5* 1.1 to 5* 1.50, well you could but scratch off lottery went with that model and lost money, and were revolutionalized when they set 5* 2.30 as very common with 5* 3.35 common - the ascension items only cost $12 USD-, 5* 4.20 Rare - $100 USD in items- and 5* 4.40 being ultra rare - $100 USD in items plus sooo many fast lane packs. Baseball cards, however, were there first. The revamped scratch off lottery just increased the per transaction cost.
To not totally enrage the F2P community you would have to change elite training & legendary training also. But I would like it if all levels of training camp, 1- 20, adopted this mechanism.
Maybe even give Elemental summons and one color training an automatic +1 to tier when rolling so 3* 2.1 to 3* 3.25 instead of 3* 1.1 to 3* 3.25. Not going to unbalance the game, minimum programming on top of the revamp, makes one color trainer better XP to recruit cost. Actually I am really liking this business model. Maybe I should quickly delete this reply ( half joking, but considering scratch off lottery’s popularity and gambling addiction, only half).
To help fill in teams missing Wu Kong & Athena ( RNG paywall) Pokémon GO have a several different mechanisms, but this post is about Gacha summons, trainer heroes and grinding past level 50 on a hero.
Note: special skill is also random 1-8. So you can summon a 1/8 5* 4.40 Joon and a Guardian Owl 8/8 5* 1.1 which just makes me giggle uncontrollably ( though probably more for lack of sleep last night). Except for special events ( and the local weather boost ) this makes the 8/8 5* 4.40 Joon a 1 in 8000 Gacha summons, on top of the already low chance of getting a Joon in the first place, but like the lottery, you are doing this to spread rumors of a friend of a friend to convince people to spend money ( now I have pictures in my head of Michael Pena talking about a guy he knows with a 1/8 5* 4.40 Joon for trade ).
I keep saying Daily Summons, VIP Pass extra summons & silver tokens are useless after Uncommon Training (RT2), until I remember you cannot get troops from camps.
But like the free mint after the restaurant meal, it’s not something I miss when I forget to collect them, and not something that costs the business any substantial money.
Late for work so… to post or delete…