I just finished my first game of Sins (Beta 2) and I am very impressed. I have some comments and suggestions based on my experience.

Questions:

What is shield mitigation? I know it goes up if you are getting hit rapidly in a short time, but does it block damage or decrease their chance of hitting, or other effect?

Can I make a capital ship patrol a sector, or use waypoints?

What I like:

The music, the graphics, the sounds. Feels very realistic.

The game is epic in nature.

The AI, when crippled, asked for peace. When I didn't give it to him, he said "but I'm still good for something!" and offered vision. I took the offer to see my other enemy. It was amusing.

The geography of the map leads to various strategies of attack, and is unique among RTS games.

What I didn't like:

I ended up using capital ships through most of the game and ignoring frigates because they were too weak to do the job. Cap ships have so much potential to be useful (especially in the right mix) even for colonizing after bombardment (and of course planetary bombardment).

I was tending to use hangers to defend planets instead of cannons because you have to put the cannons right at the point of entry to do any good (their range is too small). I'd like to see a long-range but weaker cannon I can put close to the planet, or guass cannon's range extended.

Bugs/Oddities:

It seems that some upgrades (and perhaps buildings, techs) are applied before they are built/completed. The best example of this is colony upgrades, which go into effect immediately (in terms of number of buildings possible; you can have 25/15 tactical for instance because it is still upgrading). I think the hangers also get to build sometimes without being finished. The effects of a purchase need to occur after the build time is complete.

Sometimes planets under opponent's influence, when destroyed, immediately convert back into their colony. I would recommend that when a colony is destroyed, all connected cultural lines are reset to and from the planet, and the planet essentially reset culturally (I have a feeling it would improve game mechanics anyway and avoid that glitch).

Culturally flipped planets often have buggy constructor ships or include the old owner's buildings in their logistics; it becomes difficult to develop the new planet. Perhaps when this occurs, all buildings in the sector should also convert? Similar problem when a planet is taken during construction; can't get constructors to build when I take it back sometimes. Planets flipped still project the old culture.

I believe the bounty mechanic makes pirates attack that person, or gives them ships to do it (where else are they coming from?). Also, can you collect your own bounty on a person, and would that make sense (maybe it's an extrinsic motivator to yourself)? The bounty notifications occur too often.

Black market prices are slow to change, but should instantly update the effective prices each time the user clicks. Perhaps a supply/demand model is appropriate here?

Some abilities for capital ships (like Ion Cannon) don't show additional benefit from upgrades; maybe there is information missing like the time-in-effect, etc.

The home world can have 110% income from culture. This may be unintentional.

Planet culture is always displayed 0.0 or 0.1. I assume this is because the game's not finished yet. The culture clash between planets isn't really displayed in numbers anywhere, but I'm sure people would like to know what's going on.

When a planet is taken, the old owner's extractor icons remain even if there's no building there. It can be a bit confusing, since I should "own" the territory of those asteroids now.

Capital ships set to attack a specific target aren't getting close enough to use all weapons (or at least it seems that way). However, they do seem to attack targets within range while moving around (even multiple targets).

Interface/Ideas:

Would like to see ship weapon/ability ranges somehow (A circle, or a semi-transparent filled circle maybe?).

I think the culture mechanic should work as follows: when another empire's line hits your planet, it begins a process of converting the planet (which is displayed transparently as a "cultural revolt xx%"). Multiple/stronger culture lines hitting will increase the speed of this effect. The incoming culture must be stronger than your culture at that location for this to occur (the conversion speed is the difference between yours and your opponent's).

Starting multiple research projects with no queue means you can't cancel or change the order (from what I could tell). Changing/cancelling research should be possible. Similarly, being able to change the build order of projects around a planet would be useful. Since the constructors have been buggy, it might be better to just have the planet "stream" construction materials/transports to buildings (similar to the trails on planets), sending however many it is able to at the time.

Interface: add pip marks for buildings that are under construction (or make the icons faded).

The production/income penalty based on distance from the capital is probably too much and needs to be balanced. I think instead a better penalty is lower resistance to cultural takeover. An alternative is to make the maximum income penalty 30% or some other reasonable value, but I don't think it should reduce mineral mining rates in any case. Whatever it is should be a mild to moderate effect.

The refinery and trade post work as they are, but it's hard to see how much they are actually creating. I would prefer just seeing a boost to local mining/income for each building constructed (as a +xx% bonus). However, I'm sure it's a game mechanic that you want in there (maybe so they can be possibly destroyed en route). In any case, it's unclear whether the units are moving about efficiently or if there are too many; I'd like some more information in-game about what's going on, so I know about how many to build. One possible thing to do is have it giving a percentage of the bonus based on how many of its ships successfully completed runs (so when some die, you lose a part of the bonus, as intended); that makes its effect more measurable.