It's always 50/50, this map is for me the most balanced fortress map in the game. We won a few times in defenses but it was fairly rare that we crushed our foes like on other bullshit fortress maps. As for attack, it take a lot of patience, mortar, shit tons of grenades and skilled jumper and shooter. Even without assault marines jumping into hell to distract their line of fire, a line of skilled shooter on the right side can turn the tide of the game, they will certainly not kill much because their enemies will be saved behind the fences, out of reach, but they can disturb their shots and force them to back off enough to allow the attackers to get further inside, the mortars doing their jobs at finishing off the wounded in the defenders.
I won it literally yesterday, as a pug, on LSM no less. Half the time dipshits on the team were ranting about autocannons/a baddies grace, even as we were literally stomping CSM. Main things I noticed was we had a few people dedicated to stalker bolters, we actually had people using servo skulls, and myself and a few others were on JPA basically the entire game with suicide nading (jump up, toss a nade, ground slam into the nade, profit?). When it came to B point we put real effort into pushing right side, I personally focused on securing that little inner platform area until others pushed in. I think I got some non-scrub teammates from other factions for once because people actually continued to push up. Once we had that inner platform on the right the JPA's myself included were able to disrupt their upper level while the other people continued to move up. That said this is a rare thing, generally speaking losing a fortress assault is the norm. I'm not sure if the campaign effected it leaving mostly scrubs on CSM making it easier than normal, or if I just struck gold for a pug team that game. Either way it worked out. Its not that its impossible, its just inherently lopsided, heavily. Honestly I'd rather attack Ronan than Agnathio. With Ronan even with the shitty spawns attacking the right side, or JPA'ing onto the balconies feels "ok" it feels like there is a chance you can do stuff. Agnathio on the other hand feels like shit. Attack center? you have a wall of heavy bolters waiting, Attack right you have a wall of heavy bolters waiting. Congrats thats your TWO avenues of attack. Its very easy for 30 people to hold TWO(2) choke points. I'd also argue the spawn situation isn't that different from Ronan you still have to roll up rhinos to the brides and cross them and the run time across the bridges (or pipes I guess) isn't that different from running up the ramp/lifts on Ronan. Agnathio to "have a chance" absolutely 100% requires organized pushes. It requires people grouping up, holding up till they get enough, then pushing in as a group and just using the numbers game that even if they kill a few some will get through and make headway because of it. Where as with the other fortresses so long as you keep the unorganized trickle pouring in, get people to swap to weaker flanks, etc you can get things done SOMETIMES. With Agnathio on the other hand its clan stack and group or you have ZERO chance just due to map design.
I find it much harder because most factions don't have a sniper. Plus I usually play on Eldar, and Tempest Launchers don't have the range to hit the back. I think the only effective strategy for Eldar might be Scorpion stealth suicides.
Uh, the B point at Ronan has two balconies out beside the front entrance. Those two balconies are higher up than the gallery at the back of the chamber where the defenders make the last stand. If you can get heavy weapons in the chamber and have them set up left and right of the front entrance on the inside of those two balconies, you can rain death down on the defenders.
Indeed, I think its probably more a problem with fortresses. They are pretty fun for the first half, but point B is a slugfest with you staring at a respawn screen most of the time.
Only once as Space Marines, the stalker boltor was basically needed for me to scratch that defense in the slightest. After playing that map a dozen times as Eldar and failing to even half the lives on defender tickets in most games I'm done with fortress games for good.
Imo the key is to spam vehicles after you captured A: use turrets to get rid of people on walls, so defenders will run out of tickets. That's what I hate about tickets scenarios, there are not many ways to proceed, in the end they are all so predictable...