Not much, but regular Frank is I think the 3rd best blue DD for titan use in the game (after Bobo and Athena).
The Costume is only good for the stats boost.
Additionally Regular Frank makes a neat damage stack in a rush tourney together with Jott (both slow hit-all) Since you should also have a maxed Jott for titans anyway 
Speaking of titans: Wu Kong is potentially worth it as well if you don´t have Bertulf maxed already.
And while we are at it Franz is worth EVERYTHING. As are EDD heroes (unless you have better ones in 5star already): Sergei!!!
Titan is a big topic in 4 stars. But now on to other things as you mainly were talking about tourneys and events.
Well events: The standard event team is red (because of Wilbur, which you don´t have it seems). Without Wilbur I cannot say what your best option is for events. Presumably green (Dölgöön) or blue (CGunnar). You need that spirit link if you want to score high. I don´t see Almur, so I guess just use your blue 3 star team and replace the hitters with Grimm?
If you just want to complete, well who cares? Anything works Events are easy to complete, but hard to compete. I am not much for events (I use them to farm flasks not to use them) I leave this to someone else.
Tourneys: well that would be a huge topic, but a few things:
Tanks:
yellow: Regular (or C1 depending on personal taste) Li Xiu is best yellow and great overall with C2 bonus. Worth every effort, especially since the C2 version is also great on offense (super Wizard for dispel)
Blue: Azmia (especially buff booster, not bloody)
Red: Ferant (buff and bloody)
Green: Brynhild (especially buff)
Purple: C2 (but not without C2) Cyprian, otherwise C1 Rigard (especially buff), C2 Rigard is also an option
Except for Brynhild all of these are useful on offense, too, so again, worth every effort.
Many C2 are top of their class, especially Li Xiu and Caedmon, all the healers, all the reds, which basically means nearly all of them 
A bard is basically the only way to reach guaranteed mana breakpoints outside rush, so Zhabog! (not Garyas). Bard 5%, Costume 5% and mana talent 2% (or 4%) gets an avg hero to 9 tiles. In Rush any costume 5% or 4% talent with a 5% bard will fire in 6 tiles. As you can see in rush a 5% costume with a 4% talent will fire in 6 tiles even without bard, but bards make it much easier, as you then only need 1 other condition rather than both. Since Zhabog is mainly there for the bard bonus, you can skimp on resources a bit, just make sure he stays alive.
Kalö is good enough for 7DD war defenses (in rush wars), so I am pretty sure he´s good enough for you
Other heroes that are absolute killers in 4 star world: Marcel and Bogart those 2 are real damage monsters with hard hit plus DD. Junaid is a fast strong sniper that adds a bit of healing to his special, which is faster healing than most in 4 star world.
Mana control: My favs are
Proteus, all purpose from tough bosses to wars to tourneys, with a special love for rush obviously. Worth everything, but can do his job long before that depending on how risky you like to live
Waddles: even more purposes than Proteus if that is possible and with much better stats and class This guy is way better than most 5 star heroes!
A few others are useable, but not game changers as the above 2: Hansel and Tettukh seem best among those.
Anti-minion: CGormek is the best! Others can do the job.
Other heroes out of those (that I have not yet mentioned specifically), but use regularly in wars are all healers: Anna-Belle (maybe the best of the lot), Woolerton (only fast healer in 4 star and a personal favorite of mine), D´Andre (especially for the mana boost to potentially bring fast heroes to 6 tiles), plus all the S1 costumes
There must be more than five different yellow 4 star healers and Holly is by far the worst of the lot, so go ahead and delete her 
Also not a fan of Bellerive, I tested him a lot (with Mist and jackal) to maximize his splash damage (because without the splash he is just a rather useless avg speed sniper), but I never got it to work properly, so I reset the emblems eventually. Maybe with LB2 it would work? But I am not going to waste the resources trying that He is no use without LB lets say.
Last but not least: Fun: Anastasia is one of my favorites She is useful in many settings, the only shame is that neither her minions nor fiends do anything besides being there. Otherwise she´d be one of the top 4 star heroes.
And my next fun project might be Jack O´Hare costume. In the right team I think he can be a monster
Got pretty long after all… Have fun in 4 star world!
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