Irish dancing is HARD, I will challenge anyone out there who thinks that any other form of dance is as difficult. Show me another dance style that has two different types of shoes that vary SO greatly. I think any child who takes on the dance, learns it, and is willing to show it off is a winner, hands down. Besides by the time you dress them up in all their regalia (never was a fan) I'm sometimes surprised they can dance at all!
Pointe vs regular ballet - the shoes are so different, the costumes are very different (those pointe tutus that are straight out stiff!) even the muscles you use in your legs and feet are very different. It took 2+ hours to find the right pointe shoes for my daughter, and when she outgrows these ones, it'll take another 2+ hours as her feet will have developed/changed and so will her skill level (hopefully)!