Tanatos
I think i'm not really lucky on drops, i didn't get any legendary items, and no epic sword since tie...
You won't get anywhere if you don't make little sacrifices. The 1st problem is you said you won't buy in the shop because you are keeping all your souls for Tier 15 swords. 2nd Problem you said you don't like to upgrade your current sword because it will be replaced by tier 11 once you get to the next level. Then what other options can you do? Nothing...
The solution is to buy in the shop, preferably 100 souls purchase. There at random, you can get legendary or unique swords that fits perfectly for your level and have 4 skill sets like those swords in the picture. Dont get discouraged if you get nothing at first because like gambling you can be luckier next time you draw. You can replenish your souls again by gifts and daily raids and free 3 souls.
2nd solution is to upgrade your current sword. Use the gold that you have now cause you will get more gold farming from previous levels especially 9-10(recommended) over and over.
Tip: use save souls gradually and not spend all in one go. 200 today then next week again so you won't feel so much pain losing save souls. Or if you are impatient, buy souls in limited items tab. There are great deals for souls in there and is worth it.