Thank you all for the detailed responses! The analyses are very helpful. A few follow-up questions:

1. If I am understanding things correctly then, those weapons that cost 15 draconic eyes per copy are just, um, whale-bait? It will take me about 2 years to LB3 them at this rate...

2. Consensus is that UE is the main source of draconic eye shards. Are we talking about ultimate ranking rewards here? 'cos the last UE only dropped 2 from non-ranked rewards. Don't you need to be in a top union to get those? I contribute a lot in my union (solo-ed up to lvl 51 ult in the last UE, which got us to a rank that dropped two shards) but I am not competitive enough/have enough time/have flexible enough schedule to play when everyone else is playing to go to like 700+ ult...
2a. Slightly off-topic, but how do people get such high scores at UE?! If I did my math right, lvl 700+ is well over 80 mil hp and 35,000+ in damage/hit. Our union was rejoicing that we got to 350 ult kills, for the entire event, not in a single day...

3. Draconic eye weapons is a no-go, so what do I to get stronger other than waiting for event weapons/eidolons? For reference, my light grid is Joan's elemental atk soul weapon (LB0, regalia is hard to farm), the two Nandi SSR weapons (both LB3), Sol's gun (LB1) Nandi assualt SR weapon (LB3), the rest all disaster SR hammer (all LB3). Slvl on all weapons are 20 except for like 3 hammers and Sol's gun, which are around 11-14. The next light event is a raid in May that gives bow with elaborate/defender, not a great weapon for my team if I am not mistaken (I do not have SSR Artemis, my light team is Sol, Light Tsukuyomi, Tishtrya and Michael, SR Forseti and SR Artemis as subs.) I was thinking of:
3a. Orichalcon shop weapons, although despite having what I think is a very solid light team, I can only clear GO stage 4, always lose the final boss battle >.< That is netting me just 1 orichalcon every 2 weeks...
3b. Get pink bricks from tower events and LB-up my hime SSR weapon (Light Tsukuyomi's bow is defender/assault and pretty good stats, atk at 1200+ at lb0.) I don't think I have a deep enough roster of hime to do well in tower yet (got to like 6th floor last time, and took me like 3 keys to clear it 'cos knowing nothing about tower events, I fielded my best teams on the lower floors...)

Quote Originally Posted by Slashley View Post
Oh, then what exactly is a new player going to use for other elements? Diabolos? Or the SRs from Shop (Melusine and friends)?
Actually, that is pretty much what I am using for non-light elements... Which is why I have been fielding my light team for every event so far, even though I have decent himes in other elements, too - my light team hits harder even without the elemental advantage...

Quote Originally Posted by kyc992 View Post
With Vritra event coming up next, although having a Thunder team and eidolon would give him an easy time, he probably has already spent a lot more resources on his Light team which due to the time limit could essentially mean rushing resources into a Thunder team now might not provide him better results compared to continued investment in his Light team. This would negate the immediate need for grabbing a past-event Thunder hime. With the addition of Vritra to his eidolon grid, he would now have 6 Eidolons at MLB.
That is dead-on. I actually started with wind ('cos Cybele was my best hime for quite a while), switched to dark (pulled Pluto from gacha), then after I mtix Sol ('cos I had no healers on my dark team, and I read that Sol is versatile and can work with any elements and what not), in the same week pulled Sol (again), Tish, LT and Hecatonshire (can't spell her name), so I guess the game REALLY wanted me to main light. Mtix Michael after that and poured everything into light ever since. For Vritra event, I plan to field my light team again. We did get LB3 SSR gun and LB2 SSR lance in the last thunder UE, but my thunder himes are a mess. I do have Brahma, but none of my thunder SRs seem to be good at buffing/debuffing to complement her raw power, and my best thunder eidolon is the SR from main quest, LB0. I cleared AQ3 and can clear AQ4 if I get a 100% eidolon support, so I am hoping Vritra won't be too much trouble for my light team (Nandi was a real pain for me, back then I was only strong enough to farm expert and not ultimate.)

Quote Originally Posted by kyc992 View Post
If anything, getting Andramelech before Tiamat could also be a good option considering having a fire team would greatly benefit him for the next tower. She is also a decently strong stat-stick that would allow OP to replace T. Lilim once he gets both.
Gah, I neglected that the next tower needs a fire team! Thank you for the reminder!