this is why the units from dia's batch is also useful. :3
in your case, it's Dia and Lucina, the big boobehs of their batch.

At least you can use Bran for the thunder arena.

i evolved my loch and left it at lv1. lol

you can actually use his SBB for crit team. couple him with a sparker, you're all set.

for arena, attack aoe bb is better than healing.

Anima master race.

My Lira... is ready.

if the buff have the same icon, newer buff will overwrite the old one.
example: michele use attack buff, then leorone use his buff. michele's attack buff will be overwritten. to counter this, must buff using leorone first, then michele.

tl;dr,
new buff overwrites old
stronger buffs should be used last

Focus Lodin first, and put him at first slot.
Use Emilia as Lead and faceroll your opponents.

In arena, Guardian is the lowest rank. Even lower than Oracle.
Most of the time, it's Breaker > Anima > Lord > Oracle > Guardian.

But in this case, your Emilia's LS > everyone else's.
From your list, for the arena, I would bring:
Lodin - First slot
Emilia (Lead)
Eze
Eze
Elulu

Only put Eze if he's a 6*. 5* Eze's stats are just bad.

For quests, the only units with a future, imo, are Lodin and Rashil.

she has a good 8 hitcount, but her stats are overshadowed by other units of your team.
Lodin is the only unit you can count on for Thunder arena.

The thunder element is the most balanced unit. No OP sheit like other elements atm.
Most thunder units have high health and attack, but low on defense and rec. So, the only viable tactic to use is to snipe the enemy before they even BB.

How?
Lodin - Evil Shard / Dandelga / Demon Shard / Tech Gizmo 2 / Omni Gizmo
Emilia - Tech Gizmo 2 / Omni Gizmo (might as well generate some bb since she has the highest hitcount)
Eze - Muramasa / Angelic Foil
Eze - Muramasa / Angelic Foil
Elulu - Muramasa / Angelic Foil

I already tested it. Lodin's LS is not that useful for thunder units. Most of them have shit hitcount. lol.
On the other hand, Rashil's LS >>>>>>>>>>>>>>>>> Lodin.
Static 2BC per round. I would like to use Rashil, but since it still takes a long ass time to generate bc, I might as well snipe using +50% attack.

Rashil's LS is incredibly useful if you have this ******* formation:
Lodin
Rashil (Lead)
Behemoth / Paris
Behemoth
Behemoth

Behemoth and Paris only needs 10 BC to cast their Brave Bursts.

Other special mention is Zeln (the Goku SS2 guy).. Same bb fill gauge as Behemoth and Paris.

SMP is up. :v

crystal rate is still low. it won't show up everytime.

Bordebegia, Leorone and Gravion is up now.
Waiting for Ronel.

metal mimic. evolve a winged mimic with these mats: metal ghost, king and god + 200k z.

Looks like she's wielding guns. High hitcount unit?

Just sitting here, waiting for Lira.

to add on, only fuse fodder units until your unit is lv25. after that, is not worth it.
must wait until lv100, then resume fusing bb fodder.

1. main quest is the best way. as you progress, dungeons will give better exp returns.
2. only for idols and up. for nymphs and spirits, better find at mistral or morgan respectively.
3. do more main quests. each place you clear, get 1 gem free.
do arena religiously. you get free gems for each 3 ranks.
level 3 limited time vortex dungeons give 1 gem on first clearence.
4. for 5* unit, you have to wait for thursday's dungeon. fight totems and evolve your 4* to 5*.