Probably 3 tank commanders( might want to take them in emperors armoured fist formation to give them extra cool strategems and fabulous battlecannon with fixed 3 damage) , lots of hvt with mortars and lascannons(sort of most cost effecient dakka you can spam), infantry screen, typical guard stuff. Hydra flak tanks are awesome because they add + 1 to their hit rolls against flying stuff with their 4 autocannons, and eldar nearly always have flying stuff with just right toughness to be vulnerable to 4 autocannons. Wyverns are cheap source of 4 d 6 ignoring line of sight rerolling failed wound rolls shots and they force eldar t 3 infantry to throw too much saves to live.
Tempestus scions are cool response team to whatever problem you want to solve, because there are few problems you cant solve dropping whole suicide squad armed with overcharged plasma guns into it.
If it is not strictly limited to guard, might want to leave 85 spare points in your roster to use 1 cp strategem REQUEST APPROVED for summoning fitting asassinorum agent into your army during deployment phase. He brought lots of psychic memery? Culexus time! Vindicare with recent index imperial asassins can somewhat reliably kill support characters and he can with some luck kill two characters per turn. Eversor has strategem for fighting twice and thats 16 str 5 ap - 2 attacks with reroll to wound, which sort of guarantee killing enemy character or infantry you want dead. Inquisitor might come in handy for your infantry hordes, because he provides all imperial units around him his leadership value (and he has high leadership), he can cast smite and deny the witch and he is rather cheap hq.
Also primaris psykers( astra telepathica ones, not spess muhreens) are decent support for your army, as they can make squad immune to morale shenengians, give your tanks bonus to their armour saves and make them harder to hit, and + extra deny the witch.
Out of doctrines catachan and cadian one seems most effecient, as they buff your already good stuff the best way. Cadian rerolls of 1 to hit make your shooty army even more shooty, and catachans throwing extra dice on number of shots for random stuff and removing lowest really, no , REALLY IMPROVE your mortars, artillery, tanks and flamers.
Its really preferable not to invest too much in one unit( like knight commander Pask with 3 plasma cannons or baneblade) because eldar usually have best way of countering such thing with their 9999999 psychic debuffs on your one big thing and then 23239 psychic buffs dumped on their anti tank troops)
And obvious things like good knowledge of your codex strategems, quite often people forget, that 1 cp grenadiers strategem lets your 20 guardsmen squad become exterminatus grade threat, when every man in squad becomes able to throw grenade.