Is it possible to increase the speed of the SSTP tunnel on Mikrotik?

Question

Mikrotik

Good afternoon!
Friends, tell me, maybe they came across:
There was a l2tp / ipsec tunnel server. Everything worked, but there were certain nuances, and I decided to abandon it. (connections are not permanent and when there was no connection, the server log was full of messages from ipsec) I did it on SSTP.
Classic scheme:
Tunnel server A (white ip)
Client B (dynamic (white) IP) ping to server A 9 ms.
Client C (NAT provider TTK) ping to server A 40 ms.
Speed ​​A-B - 8 Mbps
Speed ​​A-C - 2 Mbps
Measurements were not taken simultaneously.
Earlier, when there was IPSEC, rested against percents. (Models 2011 and 951Ui) now it’s not clear why ....
Your advice is really needed, how to increase the speed of A - C. (with ipsec A - C it was 8 Mbt / s)

/interface sstp-server server export
# jul/13/2016 18:12:41 by RouterOS 6.33.1
# software id = 1EQA-
#
/interface sstp-server server
set authentication=mschap2 certificate=P_E default-profile=SSTP-profile enabled=yes keepalive-timeout=10 \
    verify-client-certificate=yes

/interface sstp-client export
# jul/13/2016 18:12:01 by RouterOS 6.35.2
# software id = TYBC-
#
/interface sstp-client
add authentication=mschap2 certificate=ca.crt_0 connect-to=211.111.111.111 disabled=no mrru=1600 name=sstp_TA password=12345 user=B111 verify-server-address-from-certificate=no verify-server-certificate=yes

Answer 1

it's all?
what about configs?

Answer 2

Here is the server and client config. On clients configs identical.
I started without configs, thinking it was because of the ping...

 > /interface sstp-server server print
                    enabled: yes
                       port: 443
                    max-mtu: 1500
                    max-mru: 1500
                       mrru: disabled
          keepalive-timeout: 10
            default-profile: SSTP-profile
             authentication: mschap2
                certificate: P_E
  verify-client-certificate: yes
                  force-aes: no
                        pfs: no
 > 

 > /interface sstp-client print  
Flags: X - disabled, R - running 
  0  R name="sstp_TA" max-mtu=1500 max-mru=1500 mrru=1600 connect-to=211.111.111.111:443 http-proxy=0.0.0.0:443 certificate=ca.crt_0 verify-server-certificate=yes verify-server-address-from-certificate=no user="B111" password="12345" 
      profile=default keepalive-timeout=60 add-default-route=no dial-on-demand=no authentication=mschap2 pfs=no tls-version=any 
 >