So the game in my opinion is easily worth 20-30 EUR if not more compared to what I see around and I paid in the past. Unfortunately people are not used to pay software or music, that's a cultural problem. Also even my estimate of 30 EUR (I already give some 40 eur for the game) may be seen as little for those that sweat effort to create and support the game like GFX.
Imagine that to create gladiabots you need to work thousands of hours. For gladiabots-like quality one could let himself be paid some 30-40 EUR / hour (net income, not gross) if not more in the game industry. One financial year is normally 2000 hours of work for a single person (at 40h / week). Gladiabots is being developed for 3 years at least, so gfx has spent on it at least 6000 hours of work (if not more).
Therefore using the lower estimate of 30 EUR per workhour, 30*6000 gfx should earn 180k in 3 years. Now if the game is popular, the price of a single copy could be low, but if it is a niche game - as gladiabots is - the price is higher. That's basic supply and demand.
Say that 10k players pay for the game (and that's a lot. I believe gladiabots has much less than 10k users paying), this means that each of them should pay an average of 20+ EUR to match the expected earnings. Why 20+ ? Because steam, google play, banks and what not have transfer fees.
And all this using the lower value of one hour of GFX. 30 EUR / hour. Works as polished as gladiabots are not that common (otherwise we wouldn't be here but on some other forum) and he could ask much more as an employee. Therefore I think he is entitled to ask enough in the game, unless he asks too much driving people away.
But again, people don't realize that the one producing the work is entitled to ask for earnings, unless it is their work on the line.
Nonetheless Milkhunter (Macewindu) and BenJ have a point that the prices should be balanced on the idea: either you play a lot (but still humanly feasible) or you pay.
Now actually I don't care about unlock points for skins, but unlock points for features (campaign levels, sandbox, etc..) are important. Those features are still not necessarily to be good at the game, but they help and therefore should be balanced.
For the skin I don't think that things should be balanced. Skins are really only to show off, so one can show off also saying "look, I can afford it and I am (or my parents are) rich". Surely the skin cost should be balanced with the cost of the pack. If I buy unlock credits with 5 euros and I can unlock 2 skins out of 4, it is a bit annoying. Therefore the credit pack should at least give the possibility to unlock this or that. Or maybe one can buy an unlock pack exactly to unlock this or that (rather than getting unlock points).
Furthermore letting the players buy the single player chapters - since most of the players play only the single player since they cannot handle "public losses" in ranked - is also ok. A lot of games do this (example: Euclidea).
If one doesn't have unlock points then he is encouraged to play multiplayer, and that is nice too. (even unranked gives XP) Only in this case the unlock points given by leveling should be reasonable to unlock the single player.
I would think it is very reasonable to play 500 games for one chapter. 500 games in ranked on android (25 points each XP level) with 50% win and opponents around 1500 (that is not easy to reach for the majority of players) would be equal to 250_games*100%_opponent_score*1500_opponent_score + 250_games*25%*1500 = 468750 XP points. Or 10 XP levels or 250 unlock points.
250 unlock points for 5 chapters are 1250 unlock points (and 2500 games). A bit better than the 2000 points requested at the moment.
Also I would offer the single chapters as unlockable as one can unlock them earlier than a pack.
For the skins, once again, I don't mind. If people wants even the cosmetic for free, meh. Skins are very ultra extra pointless stuff, they may cost as much as they want. They are for rich kids, not for everyone. (unless it makes economical sense to lower their price).
Have you money to burn? Buy the skins. If not, buy the single player, sandbox, unranked and private matches, the rest is out of reach (and not needed to get better).
therefore sentences like:
Plus the skins patterns 5000 each, 4 times to unlock each, 19 different patterns, 5000x4x19 = 380000 pts
are for ChoosingBeggars (see reddit)
The point is moot as skins are for people with money, not for everyone. And that's great, as normally people with money in other games can buy advantages that compensate for their lack of skill. That is really disappointing. As unskilled people have to lose due to their poor skill, point.
Instead when people with money can show off colors and what not, but still losing plenty because they are not yet good and they cannot buy features to offset their lack of skill, then it is completely fine.