Hi,
First, I will mention a few basic things about strings that will help you find the best string. Then, I'll make a suggestion.
1. Almost every poly or co-poly string like Luxilon has less power than syn gut, multifibre nylon, or natural gut. Even all the co-poly's that have the word POWER in their name or description are still less powerful. Co-Poly strings give you more control and spin. The pros get more power from the co-polys because they can swing harder due to the enhanced control. But, if you swing the same speed, a co-poly string will not produce as much power as syn gut, multi, or natural gut.
2. Poly and Co-poly string is stiffer and harsher on the arm. Most manufacturers suggest stringing these 5 to 10% lower than your normal syn gut tension. If you like syn gut or multi at 60 lbs, you should try stringing a poly such as Luxilon around 54 lbs (10% less) and adjust up or down based on how you like it.
3. Very basic guidelines for tension: go up for more control, go lower for more power. For spin, I don't want to offer a suggestion because there are lots of opinions out there. My opinion is higher is better for spin but co-polys can give better spin at lower tensions.
4. If you play 3+ times a week, ALL strings need to replaced after 6-8 weeks if you have not broken them by then.
My recommendation for you is to try a good co-poly in the mains at 52 lbs and a syn gut such a Gosen Sheep, Gamma Syn Gut, or Klip Kicker (or several others) in the crosses at 55 lbs. I would use a 16G syn gut and a 17G co-poly. Good co-polys: Signum Pro Hyperion, Signum Pro Tornado, Lux ALU Power Flouro. There are many others but these are good. Be careful with raising the tension as polys are hard on the arm.
If you want a better string job but it will cost a bit more, use the co-poly in the mains but use a good multi like Tecnifibre NRG2 or Tecnifibre X1 or Dunlop Comfort (less $) in the crosses instead of syn gut in the crosses.
If you want more feel and power but less durability, try the softer multi in the mains at 55 lbs and the co-poly in the crosses at 52 lbs. Federer uses this type of setup with natural gut instead of multi mains.