Thoughts- by Ko0kz
Not going to go through everything I've been thinking about since many ideas have already been brought up, while others I haven't entirely wrapped my head around, but this is what I'm thinking so far.
Body blocking makes positioning very rewarding/punishing. It made me feel like there was a lot of opportunity to demonstrate both good strategy and mechanics.
The long respawn timer creates the opportunity for big MOBA style swings in the late game. Even with a significant lead, a single bad rotation or over-extension can result in a squad wipe and will let the losing team push back onto the map or even win the game before the units respawn. This makes me feel like I'm never entirely out of the game.
The short cooldown on gem collectors prevented gem collecting from feeling like a tactical decision. I felt like protecting my collectors never ranked too highly on my to do list so I would place them and hurry off or put them places I was almost certain they would be destroyed. My thought to improve this would be to increase the cooldown (and maybe even add a small gold cost), increase the harvest time, and then also increase the gem reward proportionally. That way gem nodes would become more significant points of contention, rather than simply being something you throw a collector on as you pass by and forget about.
Not all my units always want the same upgrades, but the current system forces me down a path where some will be wasted. For example, Ryme uses a lot of magical damage and both Frostcaller and Ancient Ice Frog have powerful magical abilities, but Glacial Ranger gets no benefit from magical damage. This means that if I upgrade magical damage it's entirely wasted on a my tier 1 units. Instead I might want physical damage or even physical damage reduction for my Glacial Rangers, but those don't benefit Frostcallers much at all. Similarly Terrapin Trooper and Howling Commando don't benefit from magic damage at all, but Rustborn Rhino suddenly gets a lot of benefit.
My solution would be to make armories unit specific, rather than universal. Shuffle gold costs accordingly, but make it so you could give your tier 1 units attack damage, life leach, and physical resistance, while giving your teir 2 units magic damage, cooldown reduction, and magic resistance. It would give players more opportunity to make strategic decisions like picking up up physical resistance for their melee units that are more likely to be auto-attacked, and magical resistance for their ranged units who are more likely to be caught by a blizzard or some other spell.XP at the moment feels pretty insignificant. Apart from hitting level 6 to unlock my ultimate ability there doesn't seem to be any purpose for increasing levels. My solution to this would be to replace the research facility with a talent system like the one in Heroes of the Storm. Every 2 levels certain upgrades become available and the player can select the one they want that game. Alternatively, you could keep the current research facility, but maybe remove the gold cost and allow the player to choose one of the upgrades every level after 6 or something. You could also keep the research facility and add a separate talent system, but the RF's upgrades felt like they would function well as talents. Any of those approaches would increase the impact of XP, while also creating game specific strategy.
The powerful Towers create an early stalemate phase, similar to the laning phase within MOBAs. This differs pretty significantly from other RTS games where, from the word GO, you have to worry about the other player(s) killing you and ending the game. In a game like LoL, which has a very long laning phase (>15 minutes), they made sure that there were a lot of tactical decisions that could be made and that would permanently impact the remainder of the game. HotS took a different approach and made it so the decisions were limited and the impact wasn't nearly as long lasting, but the phase was very short (<2 minutes).
Currently this stalemate phase feels pretty boring. It isn't overly long since it tends to end about the time people start building neutral weapons, but for the most part players are able to wander around and collect uncontested gems, while going about their desired build order entirely unimpeded. Tying this into my earlier point about gem collectors, I think if gem collecting took longer, rewarded more gems, and generally became a more challenging venture, the early game would be more compelling. The gem nodes would become early objectives that would create immediate action, rather than time sinks to occupy players while they wait for the action to begin.
That's about all I've got for well thought out thoughts at the moment. I'll save the rest of my thoughts till after the next PvP playtest.