Any other themes like 'Suffusion' ?

I am using suffusion from past 2 months.

https://www.ads-software.com/themes/suffusion

As my site is attracting more viewers, this theme is causing high server load.
There is something wrong with this theme as my other friends have also complained about it.
So, I wants to switch to some other theme.
Can anyone recommend me 2-3 themes with lots of customization just like Suffusion?

Any help would be highly appreciated.