Randomness: Rules changes.
Someone suggested that Warhammer40k tournament comp is often used to 'balance' the game, but I think this could be done much simpler with a few key rules changes. They might seem small, but they affect the game in a big way for the affected units.
Necrons are Stubborn:
WHAT IT DOES: It makes the necrons not as vulnerable to assaults. In the current environment, they just get run down and die a lot, but it should only be applied to warriors and immortals, the other necrons don't need it at all, stubborn 5 'cron destroyer squads would be too hard to take down in an assault.
Don't get me wrong, elite combat units will still wreck a team of warriors, and a tactical squad will tie them down for forever, but a tied down squad is not shooting, and is stuck in place. This is still better than "I attacked your warriors, and they ran away, you phase out, good game"
Tau Pulse Rifles rapid fire at 18" rather than 12":
What it does: Hey! Fish of Fury became viable again?! Well not quite, but you could use it now. The Tau codex is fine, but firewarriors suck. Before, trying to jump an enemy squad with pulse rifles just lead to the Fire Warriors being cut down in an assault (12" away) but now they can put the hurt on a squad, and then that squad can't assault them (unless they are fleet or something), though they can rapidfire back.
Dark Angels and Black Templars may use transports and land raiders from C;SM:
What it does: Gives them a way better option than their 4th edition tanks. Space Wolves, before the new codex, had this option, so i think the other subsidiary Marine codexes should get it as well, as their transports are not costed for 5th edition rules. maybe the Daemonhunters and the Witchhunters can make use of this too, but I can't do anything about Grey Knights, besides, that's rumored to be the spring codex.
Ignore GW's Tyranid FAQ:
I've not seen a single tyranid player who was happy with it. Maybe keep the doom of malanti ruling (The change to a psychic shooting attack on life leech, makes things way simpler) but ignore the Shadow in the Warp and Hive Commander rulings, neither of which makes sense, near identical wording is used in Runes of Warding and Master Strategist rules in the eldar codex, there's no reason for it to be different in the nid book.
I'm just giving this a shot, some of these may be over-powered, others may be a bit underwhelming. I haven't changed the points costs (directly) of anything, just given people some options.
Necrons are Stubborn:
WHAT IT DOES: It makes the necrons not as vulnerable to assaults. In the current environment, they just get run down and die a lot, but it should only be applied to warriors and immortals, the other necrons don't need it at all, stubborn 5 'cron destroyer squads would be too hard to take down in an assault.
Don't get me wrong, elite combat units will still wreck a team of warriors, and a tactical squad will tie them down for forever, but a tied down squad is not shooting, and is stuck in place. This is still better than "I attacked your warriors, and they ran away, you phase out, good game"
Tau Pulse Rifles rapid fire at 18" rather than 12":
What it does: Hey! Fish of Fury became viable again?! Well not quite, but you could use it now. The Tau codex is fine, but firewarriors suck. Before, trying to jump an enemy squad with pulse rifles just lead to the Fire Warriors being cut down in an assault (12" away) but now they can put the hurt on a squad, and then that squad can't assault them (unless they are fleet or something), though they can rapidfire back.
Dark Angels and Black Templars may use transports and land raiders from C;SM:
What it does: Gives them a way better option than their 4th edition tanks. Space Wolves, before the new codex, had this option, so i think the other subsidiary Marine codexes should get it as well, as their transports are not costed for 5th edition rules. maybe the Daemonhunters and the Witchhunters can make use of this too, but I can't do anything about Grey Knights, besides, that's rumored to be the spring codex.
Ignore GW's Tyranid FAQ:
I've not seen a single tyranid player who was happy with it. Maybe keep the doom of malanti ruling (The change to a psychic shooting attack on life leech, makes things way simpler) but ignore the Shadow in the Warp and Hive Commander rulings, neither of which makes sense, near identical wording is used in Runes of Warding and Master Strategist rules in the eldar codex, there's no reason for it to be different in the nid book.
I'm just giving this a shot, some of these may be over-powered, others may be a bit underwhelming. I haven't changed the points costs (directly) of anything, just given people some options.