Most high level players fight at lower levels, because there isn't anyone to fight at higher levels.

It's a pity though, because the best fights are the ones between high level bots.

If you do decide on a new build, don't sell your old items, because you might want to swap back.
Hopefully the developers are working on, and will soon be finished with the multiple-mech/mech garage option, so you can have more than one build at a time.

Ideally, this will allow you to set a preference to fight with your high level mech, and if no opponents are found, it will default to your lower level mech... or something.

Overall, if you need to sell your current mech to buy a high level one, don't bother, if you can keep your current items and still upgrade, then go for it.

When you're online, just hover over those statistics at the bottom that are showing how many players are online, how many of them are in battle and how many of them are currently looking for an opponent in PvP.
It displays nice graph from where you can see how many players are online at each level. Black vertical line in that graph marks 10 levels (e.g. 20, 30, 40, 50 etc).

When i've been online, then i've seen most players online around lvl10. The more the level increases, the less of the players are online.

That's why i currently have 3 mechs. 1st at lvl20, 2nd at lvl33 and 3rd at lvl53 (which is currently under construction; it's missing most of it's weapons).

My default mech is lvl33 mech, but when there's no-one online between lvl29 and lvl37 then i'll switch to my lvl20 mech. Rarely there's no-one at lvl20 and even if there's no-one at lvl16 to lvl24, i can always use my lvl53 mech for single player matches.

Lately, i've been using my lvl53 mech against computer. Still thinking which weapons to buy for it and also getting used to my new mech.

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Aeacus

Just a word of warning... don't finish the single player campaign! I got my level 52 mech equipped in a way that was well matched to the computer, and ran the table in single player mode. After beating the level 70 mech, if you try single player mode again you get matched against a bot with >1000 HP and 75 resistances. It totally sucks... I used the single player mode to grind and earn credits to get my higher level bots equipped. Basically dead in the water now.

It is true that after completing single player campaign, the NPCs will get much stronger.
I could suggest you the same what i do. I can't beat lvl70 NPC with my lvl53 mech, so i just have to loose until i'm able to beat NPCs again. Currently, i'm able to beat lvl59 and lvl60 NPCs, lvl61 NPC is just too tough and i'll loose to it. Few more losses and i'm facing lvl59 NPC again whom i can beat.


What lvl of mech are you building?
You're saying that you're building lvl45 mech, but your pic shows lvl61 mech.

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Aeacus

About building up your HAL, it's not as hard as it may seem. Just put the best weapons on it.
For a refrence, take a look of the replays of the high lvl players. You'll see a bunch of top end mechs there.
Most seem to go for a build that has 2 swords (for close combat), 2 artilleries (for long range combat) and last 2 weapons are your own choise (preferably mid range weapons).

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Aeacus

I think you've misunderstood what I'm telling you. I beat the level 70 mech with my level 52 build (PM me for strategy hint), completing the single player campaign. After that, it started matching me up against these insane mechs, see below. I've tried losing a few times to see if they get easier, but nothing yet. Maybe I need to lose a few more times. At least the battles are quick and I can get a few credits from losing.

My point is that you are better off intentionally losing to the level 70 mech at the end of the campaign and getting matched up against 68 and 69 repeatedly if you use single player for any grinding at all.