So. We're getting a concrete idea on what 6th edition is all about so far. Much better than expected to be honest - it still looks like shooting is king of the hill but combat has had some improvements (random charge distance is annoying but having your basic models with a threat range of 18" now is lovely. The issue of course is it could be as low as 8") and tanks, whilst more durable in the short-term (or at least, as durable) are much more fragile over the course of the game. That's huge as mech can still be important but not as important. Are fully foot lists viable? We shall see - but putting less eggs into the mech spam basket seems more viable as we look deeper and importantly, well heavier tanks are actually heavier. You can still one-shot that Land Raider but it's less likely at range - meltaguns still do it up close but with the general reduction in their threat ranges, that Land Raider has dropped more durable Terminators in your face.
Unfortunately the scenarios seem pretty bad - moving away from the 24" distance between armies, giving advantages for going first, etc. is just poor mission design so I imagine FoB/NOVA missions will still see itself as the top-mission dogs, maybe with some modifications specifically for 6th.
Otherwise though, all relatively good things. But we have an elephant in the room - the extra features. Allies, random terrain, flyers and Fortifications. Random terrain is listed as optional apparently, so phew. Flyers seem okay - if you have flyers of your own (DOGFIGHT!) or AA mounts...FAQs pending hold the key here to what becomes an AA mount. So the real issues here are Allies and Fortifications. Fortifications are the lesser of the pair here as there is a limited choice and really seem quite expensive for what they do - Aegis kits are probably going to be the most common here which isn't a bad thing as it gives armies an AA mount. And then there are Allies.
Now how Allies intergrate depends a lot on how they are worded. If they, for example, work to shore up specific 6th edition weaknesses within armies such as lack of AA mounts (we can all see the Hydra being one here yes but what are the other obvious AA platforms?) and psyker defenses, then that sounds fine and that's probably what they were intended to do. What about the armies that already bring that though? Or armies with auras? What you don't want here is people who have the capacity to answer the core questions 6th edition will ask of your army (i.e. psy defense, AA, anti-tank, anti-infantry, etc.) and then be able to take Allies for silly combinations. If there's silly combinations but an inability to deal with fliers or tanks or whatever, fine - that list has a weakness and can be broken apart by such lists. Ultimately, such lists won't be balanced and will fall out of favor. Remember Lash? Nob Bikers? Fatecrusher? They seemed OP but they weren't and when people finally listened and took those lists to get smashed by balanced lists, they stopped appearing.
However, the real issue it seems is what is being classified as Brother in Arms - aka sharing aura armies. That's the majority of Imperial armies with each other (some restrictions), Eldar/Dark Eldar, Chaos/Daemons and some others (i.e. Tau/SM, Tau/Eldar). What's leaping out at you? Sanguinary Priests? Straken? Fateweaver with Chaos (particularly if there isn't a minimum movement on MC fliers)? Etc.
With all this in mind, the initial reaction was pretty much just ignore the Allies rule for the major tournaments. It's done in Fantasy for the most part and it could potentially add a lot of silly combinations to the game, especially with Auras working for some armies. That being said, flat out banning stuff is bad, even if it makes the game unplayable. I will put my hand up to kneejerking there, particularly without any actual games with the whole ruleset. If we find after several months (and maybe a codex release), there is something going wrong with a system, the very smart minds that run a lot of the 40k blogs and tournaments are likely to come up with something that fits what 6th edition is about (like NOVA for 5th) without whole-sale changes or restrictions (i.e. comp systems). For example, the most obvious things to generate such frustations and potential problems are going to be the auras - where one model can change a whole army's outlook (much different to have Straken leading Space Wolves compared to a Techmarine grenade caddie or Imperial Guard blobs for Tau, etc.). If this is the case keeping Allies and just eliminating the "Brothers in Arms" might be a more acceptable route? It's still changing what is in the rulebook but it's not a flat out ban and is most likely going to kick the silly stuff in the nuts.
There's a lot less scope for silly without auras working but there will be more variation in list building and less "must take" choices. Things which could be common would be Imperial Guard Command squads + blobs, Eldar Farseers/Autarchs, Dark Eldar Baron/Vect, Necron Stormlord, Thunderwolves + Rune Priests, etc. etc. and it would fit with the concept of 6th edition in allowing Allies, particularly if they are there to cover general army weaknesses (i.e. psykers, Anti-Air, etc.).
In the end the best approach is going to be wait and see what comes out from everyone's playing. Are Allies just a bad system in general or are some little tweaks needed for a generally balanced game? The FAQs may do this for us - i.e. auras may be effects Army X rather than friendly models, etc. In the end, if the system works to shore up weaknesses, particularly in relation to 6th edition concepts, it's probably a good thing and something which needs to stay. In the end balanced armies are going to rule over silly combo armies and assuming such armies cannot exist without being balanced, all will be swell!
We're also starting some forum topics over on the Project Biomorph forums - what happens with P:BM is up in the air since it looks like 6th is going to be solid but keeping the forums for potential home brew stuff and generating a forum in connection to 3++ in conjunction with the chatbawks is going to hopefully benefit the community as a whole. A lot of great conversations are happening in the chatbawks for example so having the option after such a conversation to jot down some notes in a forum area for all to read make such far less transient. We'll be trying to intergrate all three in the coming days but until then, get discussing!
