How to kill the Tau Thread - Ultimate Apocalypse Mod (DOW SS) for Dawn of War

I've just gotten into UA, and THB is an amazing mod with so much distinctness to the factions and scale to the gameplay that I think I'll be hooked for a long time. I have no issues with such distinct teams being a tad unbalanced at times but I do at least need to find some best course of action to take when on the back-foot. Necrons are incredibly powerful, so I need to make sure they don't tech by hitting them hard, early and consistently. Imperial guard playing to their arty strength means I cannot have a stationary army sitting back to wait. But the Tau... now trying to play against them as SM has been a hassle for me. My gripe is towards to bottom of the Tau rebalancing thread here:
Moddb.com

Basically I find a combination of broadsides, fire warriors and skyray arty spam to be irresistible, especially when mine fields are dropped everywhere. If the skyray(s) get in range of of your HQ the fire warriors and broadsides can protect them, and I've no idea how to fight back against a prepared Tau defender wit a bunch of skyrays who is happy to sit back and bomb your HQ from afar.

I've tried:

• Assualt marines to get into melee. Even without kroots the fire warriors and disruptive skyray gunships can take care of that. No chance to catch a skyray with some melta bombs.
• Trying to get the the skyrays using rhinos. Broadsides are dangerous.
• Early rush of motorbikes to kill some generators and builders. Works, but requires a heave T1 investment into something the first broadsides will rip into at T2.
• Orb strike multiple dreads. Dreads are slow and the opponent can just micro around me.
• Librarian with word-of-the-emperor to get SM squads with long range weaponry into a firing distance of the enemy. Again, too slow, and the opponent can dance until the ability wears off. Again mines are a problem.

I'm thinking of trying out tempests with the rocket upgrade to go harass the skyrays, which after all are very weak (can't imagine how these were before they were nerfed). I'm hoping someone can show me a noobish oversight I've made. Now I should point out I'm talking about 2/4 player maps where skyrays practically have global range and can start hurting your base and servitors very early. I'm not specifically interested in SM as I think all factions struggle with early arty.

Seems to me that your main mistake is overestimating the strength of the Skyrays, by desperately sending units to kill them you leave your own lines vulnerable and give them the opportunity to kite your offending forces and distract them with kroot units. When I play against Tau in this THB version of the mod I tend to just ignore the Skyrays, they're pretty inaccurate and don't do a whole lot of damage (their splash radius isn't that large either); or if they have a lot of them then I will bring out my own artillery to counter them (Whirlwinds will out-dps them most of the time, however you'll need to get the, fairly close as their range isn't as long as the Skyrays').

Just hang back, hit their artillery with yours if you can and build up your forces. If you can (map dependent), build up a secondary set of structures away from your main base where the Tau won't have LoS so that you can build up your army without them getting hit constantly. When you think you have a large enough force, just go in for the kill - and it's quite simple against Tau as they are pretty weak on the whole so your army of Space Marines will definitely be able to endure a good few minutes of receiving plasma fire, giving you time to get to a position from which you can devastate their forces with lots of Devastator marines, Sternguard veterans, Predator MKIIs and maybe a Warhound if you have the resources.

Mid-game is probably the best time to hit Tau as SM, it's during this phase that they will be strapped for resources after expensive tier up upgrades and they'll be hurting for power if they spammed Skyrays earlier on. Your Predators and/or a Land Raider or 2 will generally dunk on any vehicles they've managed to get out in the mid game (if they still have the Skyrays from early game then they'll be no match for your vehicles).

If you want more inspiration on how to defeat them as SM, then play a game as Tau against a SM AI on Harder difficulty (or insane if you want, but insane isn't representative given that the AI basically cheats on this difficulty).

TL;DR - Don't get too bothered by Skyrays. Whilst they're annoying, they are only annoying in the same way as Nightspinners (just a nuisance, not a big damage dealer).

If Tau goes the firewarriors/broadsides route their really vulnerable in the early game. In a 1v1 you can cause a whole lot of trouble by just getting out an early Assault Marine squad or two and start to harrass them. They basically need to reach critical mass in firepower before their effective at all. Before that they just die way too quickly to do much damage. Attack priority should be something like firewarriors - kroot (if they have them) - turrets/listening posts - power generators.

I tried this against harder AI on a medium sized 1v1 map, but i suspect it will work even better against a human player. My original plan was to just hit firewarriors and power with the assault marines, but they didn't have all that much trouble dealing with turrets/listening posts either. Besides the dreadnought i got out to do that got shot down surprisingly quickly by stealthsuits. Guess the AI likes to upgrade those. You can just about ignore stealthsuits and any vehicles, they wont do a large amount of damage to your marines. In the end i got a devestator squad with multimeltas in to help clean up.

If you don't like attacking early in the game, i suggest you get a couple of whirlwinds and use them to attack their firewarriors before you move your army in to kill their skyrays. Also if you have trouble with dreadnoughts being outmaneuvered try using ranged variants. You can still drop them on the enemy lines for added effect

The first game I came across I had sat back without attacking for too long (not 1v1 as was afraid of a rush myself). I probably was too focused on the skyrays, and attempts to kill them cost me several units. The first skyray was a minor annoyance. The fifth one meant my HQ was getting very close to being destroyed with a constant stream of dying servitors costing me a lot of req just to keep it on life support; the skyrays were not something I could ignore. I am starting to think maybe the real keystone in the Tau strategy was the broadsides. They can't outrun dropped in dreadnaughts, and once they're down they have nothing to stop me killing their fire warriors; skyrays have piddly damage against vehicles.

In really intense games your only hope as most races is to wall yourself in and have enough super weapons brewing to deal with their OP titans as well as some sneaky plan to backdoor their base a bit like how one would handle the daemon hunters.