Like I said earlier, I'm playing a 'no skills that effect the player ship only' game right now. Its ironman and I take on every bounty (currently up to 200+ k and level 10's). Yes I lose ships, but never enough to not make a profit on a fight. In fact, I'm often breaking even or better just on the supplies I salvage. Only once have I gotten really beaten, and that was when I underestimated a level 10 Doom flagship. Since it didn't have many escorts, I decided to save money and not send my Onslaught in (baaad idea). Instead I sent my destroyer screen and escorts - 4 Enforcers, 2 Shades and 2 Wolves. Bloody thing popped 3 of my beautiful Enforcers in like a minute (including the one I was flying) before I ordered the other 1 to retreat and had my phase frigates harass it until my Onslaught came in and dealt with the situation.
This was NOT a case of bad AI. It was a case of me misreading the power of the enemy forces and not playing accordingly. While the AI does occasionally do stupid things, it doesn't do them any more often than a decent player does. Almost every time I lose a ship its my fault for sending it into a bad situation.
I still made a profit on the fight with 3 ships lost. And after it was all over it took me very little time to find more enforcers and decent weapons. Its almost as if how good a ship is depends in part on its availability and cost...
Earlier in the game I bought a Tempest. Damn thing cost as much as a cruiser. I decided "what the hell" and bought a Shade at the same time. The Tempest got popped the very next battle, but the Shade is still going strong. Freaking amazing little ship. Anywho, the point is that I lost the Tempest but didn't care one bit because when all was said and done it is actually a bad ship for fleet combat. It has a narrow shield so is extremely vulnerable in cross fire situations and it has short range weaponry, so is going to need to fly close to enemy destroyers or cruisers to engage. Not a good combination, to be honest. It captures points very effectively, but not more effectively enough to warrant using it over a wolf or shade.
Ironman is a absolutely wonderful and you can play in an extremely risky way, taking on all of the large bounty fleets, without a problem. You just have to actually consider taking losses and how to deal with it. On the campaign side, save up a few ships and weapons to act as a seed if disaster truly strikes. When making your fleet, weigh in the fact that ships might die and take that into account. A pair of destroyers costs about the same as a Tempest and is a far, far better investment. If you really are averse to losses, invest in field repairs. Maybe to avoid taking ship losses, invest in fighters to screen your ships.
Inside combat the way to do hard fights and avoid losses is to identify trouble spots before they happen and avoid them with orders. If the enemy has powerful ships that will pop frigates, perhaps don't deploy your frigates until they are engaged, or keep them back. If the enemy has a huge concentration in one place and a few stragglers elsewhere, pull back one place and strike the other. If a ship gets moderately damaged, retreat it or put it to use in the back lines defending an objective. If things are going badly, maybe even order a full retreat!