I used to eat exactly that, but homemade for lunch every day for years. I'm still here, but I did find that cycling home again in the evening was harder and used to keep something handy to eat around 4pm to give me what I needed in calories to get home. I had a 15 mile round trip daily for 7 years.
I used to add all sorts of things from grapes, celery, carrots, raw peas, nuts & seeds (until my work place banned all nuts due to a child having a severe nut allergy - though we could still walk off school grounds, eat and then come back in!) broccoli, red & green peppers, baby corn etc. The key was to vary the combinations and add little extras such as olives, bread, bread sticks, feta (when I could have dairy), cooked potatoes, hard boiled egg etc. Keep a seperate container handy for some dips - mayo, hummus - different flavours, even pates work.
I also found that it was quite useful as a snack option during the day because if I got peckish at 10am, I could have a few pieces from my lunch without really impacting hugely on lunch itself, but I did find it took a long time to eat it all because you will need much more veg than you realise if you are not to get too hungry during the day a few weeks into this lunch regieme.