Hemantx, question what is a SMB and what does it do?Seems like 3 is the magic number for FireSticks <grin> - I have 3 of them running at my house as well.
When I first started, I went down the custom build road and experienced the difficulties that most people do who have no clue how all this stuff work. However, thanks to the info on this and other forums, I was able to get a little bit of knowledge that has made my viewing experience much better. I'll share it below:
1. Identify which addons you really want and will use. While it may seem great to have every repo and addon under the sun - all that will do is muck up your system and slow it down...especially with a firestick. Personally, we are using SA*TS, Genesis, Pho*nix and have recently added The Ro**l We. There is a bit of overlap here, but each of these addons excels in certain aspects so I use them all. We also use Youtube and SuperCartoons. Finally, we use Spo*ts De*il and Gorilla Streams (and Pho*nix) for sporting events. Every week, I watch American Football to keep up with the local team. I watched Baseball before the end of the season. Some streams were better quality than others, but without fail - I have been able to watch every game (although I have had to change streams during a game more than once).
2. Only get your addons from official repos (you will notice that most if not all of my addons come from TVAddons - no surprise). There are other places that mass-stock repos. I avoid them like the plague after one such repo was modifying one of the addons I use and broke it. If you only get it from official repos, you only get the official REAL updates.
3. I've read all types of info on updating your librtmp file and how it can help with certain streams. This is not the easiest thing for FireStick owners to accomplish because most of us are unable to get root access to the stick. The solution is to locate a version of Kodi that has been updated with the latest librtmp file and install it on the stick...SuperCeleron has a precompiled .APK file online. I can tell you that after I was able to get it installed on one of my sticks - I didn't really notice an improvement over how Spo*ts De*il worked and that the stick itself seems a little less stable than before. It could just be me, but I am not sure it is worth the effort (at least on the FireStick anyway).
4. Skins - some skins work better than others on FireTV Sticks. The ones with all the intense graphics may overwhelm your device. We use Arctic Zephyr (with the menu choices we want/need - it is very easy to configure).
5. Buffering - this CAN be an issue. We found that a few minor adjustments in the AdvancedSettings.xml file along with an account over at real debrid has made this a very minor issue for us.
Finally - all 3 of our sticks use SMB to share files on a PC hard wired to the LAN. We use this same PC for mysql to keep our library consistent across all devices. We have everything listed in Trakt.tv and this also works on all 3 sticks.
Hopefully, this will give someone a little help.