Hi Jo,
I live in Vaud, and understand how you feel about visiting the same places with visitors all the time. Gruyeres isn't quite the same on your fifth visit.
I always find Ticino to be an
excellent place to go for a weekend holiday. You can get to Locarno quite easily from Lausanne: take a train to Domodossola, then take the train through the very scenic Centovalli region to Locarno. My personal favourite town is Ascona (near Locarno), but Locarno, Bellinzona and Lugano are also quite nice, and nothing is very far by train. The Valle Maggia area (accessible by bus from Locarno) is breathtakingly beautiful, and the food in Ticino is great.
Personally, I find Milan to be quite unattractive and not that tourist-friendly, although I have to admit the Cathedral is impressive. As someone already mentioned, it is a very easy day trip from Ticino if you'd like to go.
One thing to consider is that there might be a lot of things closed for business over the Easter weekend, seeing as Ticino and Italy are Catholic places. However, I'm not totally sure of this, as Italians are a bit more open to Sunday shopping, etc. This might be worth looking into before you commit to travelling there.
HM