First of all, I'll assume that you don't have all the parts yet, correct?
Secondly, if you haven't yet, it might be good to at least read this thread at least once:
http://ravenrepublic.net/forums/showthread.php?tid=239
Now onto your design:
Since I don't know which parts you have yet, I can't really tell you what to replace.
However, one glaring area that can be helped here is your tuning.
There are several more efficient ways to tune. With the head for example, tuning for ECM does not really help, and since ECM is banned in pretty much all tournaments, there's really no point in investing in it.
As for your parts, try to avoiding investing too many tuning points to weight if the parts you're tuning are already light to begin with. Parts that have deficiencies in certain areas (i.e. defense) will benefit most from tuning that deficient area. In this case, most of the parts you equipped are already light to begin with. Hence, they don't benefit much from weight reduction. In most cases, it's only worth tuning the weight of the heavier AC parts.
Since you're using an overboost core, a better way to tune this AC is for you to spread your tuning points between cooling and defense.
Now onto your internal parts: LOTUS as your generator and GULL as your booster is a great choice. They were practically made for each other. The LOTUS' low calorific value compliments the GULL's high boost heat.
However, let me point out that the single most important stat in a generator is its output. Its output determines how quickly your generator can recharge your energy. Capacity is simply how much energy your generator can carry. In the case of LOTUS, its output is not as high as the other leading generators. Hence, it'd benefit you more if you placed most of your tuning points on output instead of capacity. And don't worry about LOTUS' capacity. Though its capacity stat is low, its redzone (compressed energy) is very large, which effectively increases its endurance by much more than most people realize.
HAZEL2 is a decent radiator until you get your hands on ANANDA. Well for now, it'll do. Radiators are meant for one thing: cooling your AC. Hence, the most efficient way to tune this is to give all/most of your points to cooling. If you want a lighter radiator, try HAZEL, with all tunes devoted to cooling.
This may seem like a lot, but don't worry. You'll get the hang of it. We'll be here to help.