This reply is a bit speculative because I don't have any experience on the non-mobile publishing side of things.

I doubt a PC release will have any impact on console sales, as the two markets are pretty isolated from one another. Lots of game developers play games on PCs and consoles, normal users typically don't.

However, a PC release might limit your ability to negotiate a beneficial exclusive (or timed exclusive) console release with one of the big manufacturers. If you have limited reach and marketing budgets, then exclusivity might be a good way to get some level of featuring and visibility in the online stores. It might be worth talking with your Xbox/Sony/Nintendo account managers before releasing on PC to make sure you're not missing out on any golden opportunities.

Staggered launches tend to have a more difficult time for major games. They cannot share a marketing and social media push, cannot share the 'network effect' of people talking about it with their friends. Depending on the brand and product lifetime that may not be an issue, or it may be a critical issue.

Staggered launches for hobby projects with no marketing behind them may get a slight benefit. Since mobile app stores have around 1000 launches per day, there is a very slightly higher chance they will get noticed if they've got multiple staggered releases.

If you're working with the major publishers for a console release, your contacts at the companies can discuss release dates in depth, with concerns about what other products are releasing on the same date or nearby dates.

Thanks you very much for all yours info :)

about the piracy... general consensus on similar discussions in the past was, as long as you are a small dev without the money or power to really go after it, to just stop caring about it.

There were some interesting experiments by some devs that were able to get some quite exact numbers on how many pirated versions floated around, and made some interesting assumptions on lost sales.

Generally speaking, most of these devs were speaking about MUCH lower numbers of lost sales (single digit percentages)... most of the pirates wouldn't have payed for the game in the first place, and as long as pirating a game is not that easy (for example needing a separate download), while getting the game legally is easy (for example it is available in all parts of the world, not some "US only, screw the rest of the planet" sh*t) and the price seems right (no "lets add 20% because the swiss can afford that... hue hue, gotta love currency exchange games!"), most people really interested in your game will pay for it. You got to remember that the official numbers thrown around by the big shots in the entertainment industry are overinflated on purpose, they want to force politics to continue a fight not even the mightiest government in the world could possibly win.

You don't get the US Senats attention by being honest about how much damage piracy is causing. And to be honest, they have a point. Every pirat is one too many. But the point is, the money lost to piracy is most probably not as high as they make it look like.

Given how impossibly hard it is to defend against piracy, best stance seems to be to not worry too much about it, and concentrate on making the paying customers as happy as you can.

Concentrate on players who pay the bill, not the freeloaders. As long as you are no creating a free to play game, that is.

Aside of piracy, some PC players might hold off for a Sale, because these have become pretty common on PC, while still being a rarety on the Consoles... so you should factor in a lower average income per copy sold on PC.

I read somewhere that some analysts think that in two years time, there will be unhackable DRM, hence the end of piracy as we know it. Given the track record of DRM in the past, I believe that when I see it. And given how strongly some players hate DRM, you will loose sales either way.