IMHO, if game required you to pay 5-10$ per month to keep up with upgrade, many more people would buy/play. Fact that you need 50-100$ per month in order to properly gear, or like many F2P spending 24/7 hours per week to grind the game and users (from dias) makes this game not appealing to mass of new players.
Game has a lot to offer, but reworked CS could in turn generate more money for Frogster if prices are more reasonable and you can fairly progress in game with less spent per month.
I am very doubtful that FEU will ever do any of those. They don't even have slight idea what should be in CS and deals are just getting more annoying, even for those who don't care to spend cash on ridiculous prices.
Again, naming no games here, there are a couple which I've played in the past which the developer/publisher have changed from *very* limited F2P/subscription models to widely F2P/subscription/game card models. They're quite successful and are almost continually expanding. However, and this is a key difference: Neither of those games have items in their item malls for modding gear. Those games are *not* gear-modding games, and never have been. This is one reason why they were able to change to their current payment models. The subscriptions to these games provide a certain and specific number of store "points" per month to the subscriber, based on the subscription type--standard monthly or premium yearly--which can be spent on mainly "cosmetic" mall items. There are *no* items available that will permanently give a character a combat advantage in those games.
As I said previously, I do not think that Frogster could easily change their payment model to include a monthly subscription which includes a specific amount of diamonds every month which can be spent in the Item Shop, however attractive to the players this might be. It would be a bear for a relatively small company to manage, not to mention that it would need to be managed across three sets of regional servers (EU, NA, and AU.) Toss in the availability of various "diamond" cards (mostly different for all three regions), along with other diamond payment methods, and the perils to the players of using those methods.
IS prices are relative, and I've stated that yes, there are some items whose prices should be adjusted. However, considering the number of calls by players for "balancing" the game, perhaps increased prices for some items may be justified. After all, if you've purchased a diamond package, Frogster has already received your money. They get no additional money when you use your diamonds in the Item Shop, right?
But players with large amounts of disposable income (the "haves" or "1%") have a distinct advantage, in either PvE or PvP, over the "have-nots" who have less, or no RL money to spend. This is a fact, not an opinion. For example, I personally cannot afford to buy up transmutor charges in the IS so I can take a weapon up to T10 or T11. *That* is a fact which I must live with, and while it doesn't have a huge effect in PvE, it *does* in PvP (Guild Siege). I simply cannot be "equally geared" against a similarly-leveled character played by someone who has deep pockets. They have the advantage and ability to dig into those deep pockets in order to buy things from the Item Shop, or "sell" those diamonds to others for gold, so they can either buy gear or stats from the AH and improve *their* gear for Guild Siege and, obviously, for farming instances in order to acquire even better gear. I simply cannot compete, gear-wise. But I don't grind my teeth over it, or complain on a daily basis on the forums. (I'm not going to call anyone out here, but they know who they are.)