Okay... here's my take... but you might or might not agree with me :)
Bear in mind a lot of assumptions are being made here!
Right now you have your 70k player but are still 4th, and not really dominating your league. 4th is still decent though.
What I find very alarming is your net income is - 2.7k. I play in a small country myself, so I've never had to work my butt off from the lower divisions and move up.
I really don't think that you require a 70k player at that division, but i've not looked at the other teams in your league. Firstly the income is insane and costing u to sell other players to cover the cost. Think about it this way, if you have a "A ++++ shooter" being defended by a "C defender", he'll score... but so will a "B shooter" who prob cost you 1/10 his price.
Bear in mind, you're not scouting atm. I'm assuming u stopped because you found a few players you like. Next season, when your players go up in income and you scout again, you'll be about 30k (estimate) in the negative every week. Which is not healthy for a young team that wants to build up.
What I would do personally is this I would sell that center, and buy two 10kish players. I'm not sure how much u can fetch from selling him. Since you are training guards, perhaps a strong SF with skills that a multi dimensional so u can play in more than one role. Then save the rest of the money to put into your arena.
If you are looking to build a team, it is a good idea to invest in your draft and pick up some nice players or buy strong trainees. This will give you a long term team that you can build up and move on to the higher division. And perhaps even the one above that when your trainees mature. I'm not one who is insane over super high potential players, but I'd look into getting an 18 year old all star with a nice skill set. And aim for promotion in 1 - 2 seasons.
Right now, being negative -2k (possibly higher later on) isn't a healthy long term prospect.
Just my two cents and my own POV. I'd suggest asking around to get some other opinions too : )