Hi, welcome to the forums
I noticed your username is your email and I'd probably change that if I were you, as it end with your email address being added to a lot of spam lists, or having people directly email you random things instead. It might also make it easier to compromise your account. You can change this by going in the top right corner and clicking your profile name, and then "Edit Profile". Then select the first "Edit" next to the Account section.
With regards to your question about champions, I would focus a lot on building a solid Dragon team, as you mention that you have gearing issues. Looking at the stats of Deliana, I suspect this is indeed the case, because at +23 speed she is very slow. Much too slow for starting to jump into more content.
At this stage of the game, every one of your champions should have boots that primarily have a speed stat, even if the other stats are garbage. Don't focus too much on building sets yet, just focus on having gear with decent primary stats. Other examples would be gloves with crit rate for damage dealers, or hp%/defense% for support champions. Body armor should also be hp% or defense% unless you are specifically building a high damage dealer for arena.
Where are you up to at the moment in the Dragon dungeon? Deliana, Kael and Apo are the foundation of a solid team that should take you up quite high. Altan can also bring some value, but I probably wouldn't 6 star him just yet. Instead, there are 2 epics in your team that I think will provide a lot more long term value for you:
- Toragi the Frog - An excellant support champ that will go a long way to keeping your team alive. The 3 turn ally protect will be very useful for both Dragon and CB, along with the poisons and decrease attack. The provoke is also useful for the initial waves.
- Venomage - A great poisoner that also brings decrease defense and decrease attack. Will also reduce the damage your party takes by 15% for enemies under heal reduction. Another great champion that will likely be with you through most end game content
Personally, I would eventually take both of these to 60 first (probably doing Toragi first) but at least get them to 50. Then I would run Dragon with Deliana, Kael, Toragi, Apo and Venomage. From there, you really need to start to sink some time into Dragon to get decent gear.