Suggestions to improve gameplay based on complaints I've heard in alliance
Complaints regarding the new economy.
The current economy is not exactly great. While it does allow for more unit coverage early game and a small rush potential, every game ends with a 400 tiberium surplus, and it is actually in your best interests at around mid game to send your harvester off to its death so that you can have more units on the field.
Economy is something that you should always be left wanting just a little bit more of. Too much economy leads to imbalances in that cost effective units tend to fall to the wayside as cost efficiency isn't an issue. Commanders with low cooldowns and higher ability costs also become more useful than those without.
Feeding into a no harvester build is kind of like not building SCVs in Starcraft. Besides being necessary, they are a strategic target for the other player. In this current patch we're seeing things like a missile squad walking into a tank, and then there being a boring unnecessary game of chicken as both sides don't build harvesters. Having no harvesters in play really screws up many map, commander, and unit dynamics.
Complaints about the new units.
The Juggernaut and Giga Cannon are not balance tested. These units are both superior derivatives of other existing units (Juggernaut being a superior version of an MLRS, Giga-Cannon being a superior version of the Basilisk). The Giga-Cannon, despite not being strong against infantry, still practically insta-kills them anyhow.
Complaints about reasoning of unit rarity changes.
It seems there is a bit of circular logic at foot here. For example, in the Disruptor comments, it is said "Simply being a long range unit isn’t enough to be considered Epic", and yet, Sniper teams were upgraded to epic? Another comment, "Making Sniper Team Epic also frees up space for a different Rare anti-infantry unit to join the Barracks", why would there be any limit to units that you can develop? The only thing that should seemingly need changes is the UI to accommodate the new portraits. More, "The Confessor’s breadth and unique buff to allied infantry make it unique and impactful in a way that warrant its rarity increasing" which really doesn't match up to its real world status of getting chewed apart by two venoms, or being handled comfortably by two rhinos. In my eyes as a player, they require an expensive tech building, are expensive themselves, are a very niche unit, and suffer the opportunity cost of much more playable and affordable units, not something I would hope for from a rare unit.
Fairness in matches.
It was unfortunate timing to go into release mode before implementing the fair play patch that was being alluded to. Currently, people are being put into all sorts of squash matches. Even one unit a level above can make a huge difference, just ask the guy trying to use lv7 missile troops to ward off lv8 rhinos, or ask anyone that has lv7 attack bikes what they think about lv9 banshees and pitbulls (which kill 1 bike per shot).
With currency involved now we are seeing people with entire lv9 loadouts - and being matched versus them. Pretty much a waste of time, and we are still in need of a concession button, no reason to have to close the game to try to get onto another match.
The one that is going to suffer from not doing this ultimately isn't going to be us, it will be the dev team. The amount of bad press and user dissatisfaction with the game being mobile is more mammoth than the tanks. To quote a very random comment to a very random guy on my YouTube channel "I say go f* yourself both of u for playing this s* game". That's the attitude that you have to overcome, and you need to do your very best the very first time or there will be an absolute s*storm of bad sentiment from people that aren't quite as sympathetic as the pre-alpha players. Every day counts.
This also extends to mechanics within the game itself. We really don't need instant 180 snap around nukes, for example.
I'm sure Jade and others will be able to comment more.