Im currently level 58. My go-to team at the moment is ezio, riley, ulfang, garrick, cara. They've done me well so far. I also keep my flora and ariel leveled as backups.

However, I've been experimenting with slim, gizmo, and leah. I like all three, but its getting expensive to keep everyone leveled. Who should i focus on? I also plan on getting xanos and jasmine soon. Obviously jasmine replaces flora, but are there any other swaps i should make?

You're team is full on psyhical.
1)Ezio is 100%
-good damage,good dodge and good life steal.
2)Riley is good early on.
Good damage,2lifes and that wolf form.
The problem is that 80+ she falls apart and becomes only good at CoF.
I replaced her with Xanos,who is doing his job as a DPS hero.
3)You don't need that pile of trash Ulfang.
Jasmine is a good healer and stunner + the shield.
Get her,but then again she falls apart at level 85+ .
I wount replaced her tho.
She is just so good to pass out.
4)Garrick.
Damage.
Nuff said.
5)If you want Cara in you're team,h er fourth ability is worthless.
But she does one shot people,so there is that.

Also:
-Work on Gizmo.
Why?
Damage.
-Leave Ariel.
In the late game,which you are entering,she becomes an energy feeder.
Slim shows his potential at level 75+,so wait on him.
Leah also a late game hero.(level 70)

Alright, thanks. The reason I like Ulfang is his team buffs. At the start of the round, he gives speed and attack, as well as lifesteal, which are great for things like arena and CoF. I agree he's probably my least useful though

At your level I would just focus on a CoF team.
Riley, Leah, Jasmine, Ethera, Gale (90 CoF team)
Make sure you have an up to date Arachna once you hit 90 and get started on her awakening quest ASAP.
She will change your game =)

Based on the heroes you have now, work on Gizmo, Leah, Garrick, Riley, and Ezio. Keep in mind you are also lacking a good tank. Both Ezio and Riley are front line DPS heroes. As soon as they're down, your opponents have an open shot to kill the rest of your team. So work on Drago right away; he's a great tank—if not the best. I also find Leon very useful, but make sure you work on Drago first then Leon if you'd like. Also, work on Jasmine right away when you get her. She's very useful. I use Jasmine as a support and a healer, not a DPS. That is why I only have her at 3*; she gains her ultimate much faster that way, and she's amazing at disrupting enemy ultimates in the CoF and great for countering physical heroes for her blinding effect.

Other Suggestions: Riley isn't as useful at higher levels in the Arena. So if the Arena is the most important aspect of the game for you, wait on her—but, Riley is still very useful in Raids. She is also useful in the CoF, though she is not in my CoF team.

Ariel shines at lower levels, but her power diminishes later on. You can work on her until you hit around level 70+ if you have the time and money. If not, drop her.

Drop Ulfang.

Leah and Gizmo work best at higher levels. Gizmo deals a lot more damage when he's in orange fusion and his gear is fully enchanted—same goes for Leah. Both of these heroes I began using at higher levels and I highly recommend.

I recommend you keep working on Cara. She's not crucial at your level, but she's a must have later on, in my opinion. She's great at countering physical heroes (as expected), she's great at countering tanks, and she's an especially great counter against Ezio, Garrick, and Riley. She also makes the CoF a lot easier and faster for me. At orange fusion, she gains +400 energy after every battle, so her ability is almost always or close to ready for the next battle. Once the tanks are down, everything is smooth and easy. Also, I disagree with Mochokara; Cara's fourth ability is very much useful. Her Nighmare ability has saved my team a lot of times