MR13 for what if I may ask ? if you like tanky frames Nekros and Nezha are pretty good tank frame with nezha being also quite agile compared to most.Saryn while a very good frame is not really tanky but if build right does tons of dmg.Galantine Prime is also a very good weapon indeed.
I am MR15 almost 16.
I have frame wise : Nyx/Prime - Ember Prime - Frost Prime - Volt/Prime - Nekros/Prime - Valkyr/Prime - Titania - Hydroid - Ash Prime - Chroma - Saryn/Prime - Nezha - Ivara - Loki Prime - Nova/Prime - Oberon - Banshee - Equinox - Mag/Prime - Trinity Prime And Excalibur.
Weapons to damn much to name. But most used are ( depending on frame )
Primary:Soma Prime, Sobek, Cernos Prime, Rakta Cernos,Sancti Tigress, Tigress Prime,Hek, Vaykor Hek,Ignis,Grinlok,Braton Prime,Zarr.
Secondary: AkLex Prime,Twin Rogga,Secura Dual Cestra,Despair, Spira/Prime.
Melee: Galatine Prime, Scindo Prime,Nikana Prime,Broken Scepter,Secura Lecta,Glaive Prime,War,Kesheg,Orthos Prime,Furax Wraith.
I Own a whole lot more weapons then that but those I use most depending on frame and situation I find myself in.
I have been playing warframe since update 7.4 so yea.With the exception of Ember Prime and Valkyr Prime everything else is farmed. those are the 2 only one I bought as prime access when they came out ( ember prime was my first prime ) everything else I have farmed for. That includes the slots and forma and what not.(before relics came the Tower keys was the thing and farming Forma was a whole lot easier then too ) I stacked up on mods parts and what not sold a few frost prime sets and ember prime sets amongst a few other things on a later date along with a ton of vault run mods to get the platinum and trade as much as I can everyday.
If you ever feel like you need someone to help you grind or level up or fetch you something feel free to hit me up in game.
In game Noryg or add me and see when I am on or send me a PM here and ill give you my Steam you can add me up on that and send me a msg.