Depends on how many gardas we're talking about and what other kinds of units are on the field.  Bombers can take a certain amount of fire from flaks and still fight effectively, but if we're talking about huge formations of flak frigates then bombers are not an ideal unit.  Destras, Illuminators, and Disciples are much better choices against a garda-based fleet.

Advent is actually the best-equipped faction to deal with missile barrage.  The simplest counters are to use the "detonate antimatter" ability of the Radiance battleship or the "reverie" ability of the Revelation battlecruiser.  Both of these abilities will stop missile barrage instantly.  The other alternative is to combine guardians with a Progenitor mothership.  Use the guardian's special shield ability to reduce damage to your fleet, and then continually use shield restore to replenish your units.  You can actually survive missile barrage without taking damage by doing this.  Be careful, though, if the enemy disrupts your Progenitor it can turn VERY ugly for you.

So what would be a good starting fleet? I always use 2 Halcyons but lately this hasnt worked as the Halcyons lack the firepower to do anything serious and even the supporting frigates don't do much.

Hmmmm Ok thanks for that Info. Now i hear that seekers are actually good for combat i never use them i thought they were worthless to what extent are they good in combat and should you start out building them or start out with disciples?

Ah ok. How would you use Aeria Drone hosts and Destra Crusaders what role should they play and what ships should they be partnered with?

If you just plan to play SP, you don't need to worry about anything that has been said as far as types of units to build (seekers/discples/blah blah) or capships.  Just build what you want to build, and win.   You like that Revelation battlecruiser?  Just build it, or several of them.  You like something else?  Just build that.  You like carrier cruisers?  Just build them.

However, if you plan to play MP, what Darvin is saying is VERY significant, so listen to him.

Not in that order, I hope.  Radiance is a poor choice for first capital ship.  Typically you should either pick Progenitor or Halcyon as your first capital ship as Advent.  Sometimes you need a Progen or Halcyon, but after the first pick you generally can't go too wrong with picking caps as Advent.  They're all pretty solid.

If your opponent has lots of strike craft, or your fleet starts getting very large, you should seriously consider the Halcyon.  Its telekinetic push ability lets it swat away strike craft with ease, and its energy amplification aura increases the damage of all nearby frigates, making it invaluable to a late-game Advent fleet.  Early game, its Adept Drone Anima ability gives it more punch in combat by giving it additional squads.

Typically you either go all destra or all illuminator; 50/50 really doesn't work out all that well.  You should also be working in the guardian support cruiser.  He can protect your entire fleet and make them take reduced damage.  Combine this with your Progenitor to restore shields and you've got a monsterously powerful fleet at your disposal (this is commonly called the "battleball", as Advent players will bunch up all their units into a tight ball to fit into the guardian's special effect radius).  If you go with illuminators rather than destras, you can use the "repulse" ability to literally push enemy units away from your fleet.  Only units that outrange the illuminator will be able to attack you, which is very useful.

How many bombers you talking about?  If it's just an enemy carrier capship with bombers, make all fighters on your skirantra and that's all you will need.  But if the enemy is darkening the skies with bombers from a bunch of cruisers, your skirantra isn't going to come close to cutting it.  You will nee a bunch of carrier cruisers yourself, loaded with fighters.

Sentinals do kill bombers, but not that well.  Under most circumstances you'll need fighters.

1. Culture is important, and the good think for Advent is that if you have a volcano or ice, you have to build 2 civ labs, and communion temple research requires 2 labs too.

2. If you have 5+ planets, divination

Knowledge aggregation

and eyes of the believers or something like that

3.

4. DOMINAS + CRUSADERS + GUARDIANS+ LUMS

2/1/1/2