Well, optimal settings usually means the best for your graphic/processer.

Best also usually means what it says.

What i recommend you doing is eventually reducing your resolution to at least 800x600.
There may be other tweaks to the settings, like turning off shadows, bullet holes and ragdoll effects.
Disable Anti-Aliasing and also Filtering.

Usually if your laptop is good enough, it generally only needs resolution tuning, just by lowering it the performance increases. Try these out first, any other console command will only reduce the visual detail, which might reduce your overall satisfaction of the game. So before i go there, try the settings above first

try these.

r_desaturation 0
r_specularcolorscale 0
r_normalmap 0 //
r_smc_enable 0
r_multigpu 1
r_distortion 0
sc_enable 0
sm_enable 0
r_dlight_limit 0
dynent_active 0
snaps 30
cl_maxpackets 100
rate 25000
cg_nopredict 0
g_antilag 1
r_drawdecals 0
r_lodscalerigid 4
r_drawsun 0
cg_brass 0

these also include commands for online play, basically reduces everything to almost nothing