I'm sorry to hear about your illness, and all the sorrier because it has affected your tour. My nervousness about my asthma (specifically, what might happen if I have an exacerbation abroad) has been one of the factors which has prevented me from travelling. But i suspect, from your description, that my asthmais more aggressively medicated than yours.
You are right to be cautious of alternative approaches. As far as I am aware, there is little to no evidence of any benefit from any of these therapies.
I'm not familiar with Dulera, but a few minutes Googling tells me it is a combination inhaler, with a Long Acting Beta2 Agonist and Corticosteroid. These are very popular right now, and the most used seems to be Seretide, which combines salmeterol and fluticasone propionate.
There are a lot of positives to having a combination inhaler - not least only having to keep track of one, rather than two - but I found that the escalation in my Asthma Plan had too few steps with combination, whereas we had more options with maintenance doses and escalation if separated (though I am on an extremely high dose of both for maintenance).
Other alternatives you might wish to explore can get you away from inhalers to tablet form. Theophylline can be very effective, and I found it good in combination with my inhalers. Unfortunately, it is related to caffeine, and can cause disturbed sleep patterns. It certainly did with me, as I was spending at least two hours awake each night, which was unsustainable. OK, so I know I'm typing this at 5am, but that's beside the point
Another oral medication, which I take now, is Montelukast Sodium (Singulair etc), which seems to have very few side effects, though there can be serious mood-affecting ones.
It is usually used in conjunction with inhaled steroids.
I have to say that I utterly hate steroids - inhaled and oral. But they are effective, and there is no doubt that my life would be very different (or ended) without them. So I reluctantly include them in my regime.
And the inhaled steroids have fewer of the nasty side effects than oral ones, so it's in my interest to maintain my high levels of medication to stabilise my condition as far as possible.
I hope you can find a solution that suits you, and lets you get on with life.