Shivan ships have low hull strength, but strong shielding. Shielding regenerates over time. Hull integrity does not.
Compare and contrast:
- GTF Erinyes - 500 shields/325 hitpoints
- GTF Ares - 650/425
- SF Dragon - 700/100
- SF Manticore - 500/100
- SF Mara - 620/200
- SF Basilisk - 950/100
- SB Seraphim - 1600/500
The way things are balanced, guns run out of energy much faster, but do much more damage (only two weapons are really spammable, and one of them has limited ammunition). Rearming during a mission is not possible, though secondaries are more powerful.
Because of these differences, Shivan ships fly differently to GTVA ships (would likely be boring if they flew the same, right?). Tactics used when flying missions must also be different.
Hit the enemy fast and hard, though you will need time for your guns and shields to recharge between engagements. Use missles sparingly, since they are limited. Retreat when your shields are low and find cover near friendly fighters and/or a capital ship. Heroic solo charges at enemy wings is no longer an option. Wingmen are more important. Lateral thrusters can give you an edge in combat.
I hope this helps.