drugs can't be taken more than once for the benefits anymore, so you'll only ever see +1 from cigarettes, and Demolition expert is only good for increasing damage of tnt and c4. Make sure to get bonus rate of fire as well because frags cost 5 ap to throw while plasmas cost 4 ap, and I'd say only about 120 or so to effectively hit people with grenades
Thanks for the answers. Also I'm reading STR effects throwing range is this for grenades too?And heave ho perk?