I would suggest, "The Three Tenors", which is a fairly new piece aranged by James Christensen. It's actually written for 3 Tenor Saxes, but we kiped it for three euphs. Tenor arias sound much better on euphonium than sax don't you think? (In fact anything sounds better on euph than TSax). The themes are "Vesti la giubba" from I Pagliacci; "Funiculi, Funicula"; "Torna a Surriento"; "La donnas e mobile" and "O Sole Mio". I would rate this between a grade 3 or 4. Fairly easy.
We gave a copy of the TC Baritone part to the tenor sax so she wouldn't feel left out.
Miraphone 5050 - Warburton BJ/RF mpc YEP-641S(recently sold), DE mpc (102 rim; I-cup; I-9 shank) Symphonic Band of the Palm Beaches: "Always play with a good tone, never louder than lovely, never softer than supported." - author unknown.