Too much! WAY too much!
Another first cycle that has 700+ mg per week (710 mg actually)! What makes people think they need these dosages for first cycles?
Your little brother does NOT need to use this much gear for a first cycle! The avearge young, healthy guy makes somewhere between 3000-3600 mg of testosterone a year. Your little brother is planning on this in just 3 weeks!
For a first cycle, I'd recommend cutting those proposed dosages in half, and preferably even less. As an example, my first cycle was 10 mg of d-bol a day, one tenth of what you propose, and I gained over 20 lbs in 6 weeks.
Nolvadex is going to be the best protection against gyno as this is a Selective Estrogen Receptor Modulator (SERM) meaning that it has the greatest affinity for breast tissue. If gyno seems like it's going to be a problem, I'd use it all the way through the cycle, and for 4-6 weeks after, 20-40 mg per day. Arimidex is an aromatase inhibitor that will help with overall water retention (and there will be plenty on this proposed cycle!) by inhibiting the aromatase enzyme found in fat cells that converts androgens (like d-bol and test) to estrogens (hence the water problem). You might start with .5 mg per day, and continue this for 4-6 weeks after the cycle, too.
Xcel can tell you better about letrozole, as I've no experience with this compound.